ENVS4000
What are Cold Regions?

Cryosphere: regions on earth that are affected by water in the frozen state, whether seasonally or permanently.

 

Includes regions with ice sheets, glacier ice, permafrost, river ice, lake ice, sea ice and/or snow.

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Cold regions are extremely sensitive to environmental change, including global warming and pollution.

 

*Relatively few measurents of cryosphere exist due to geographical remoteness, large scale, extreme conditions, and the long time-scale of some cryospheric processes.

Evidence for Recent Climate Change (10)

-T and P records

 

-Unusual weather patterns

 

-Glaciers

 

-Coral reefs dying

 

-migrating species

 

-pests and diseases

 

-arctic sea ice decline

 

-treeline migration

 

-longer growing season

 

-permafrost melting

Swiss Glaciers

Glacier Du Trent (Hester’s first glacier) retreated 700m in 19 years (37m/yr)

;

-In 1985, 48 glaciers advancing, 42 retreating, 14 stationary (Switzerland)

-In 2006, 1 advancing, 84 retreating

;

-B/W 1850-2005, 50% area loss for all Swiss glaciers (15%/decade since 1985)

Why do Glaciers Matter?

-contain 90% world’s fresh water

-one small glacier (1km2) contains water for 70 000 for 1 year (for Canadian water use of 300L/day)

 

-In dry years, glaciers contribute 55% of the Bow River summer flow at Banff (up to 80% in late summer months)

-Due to retreat flow reduction could be up to 70% by 2050

 

-Over a billion people rely on cryospheric water from the Himalayan snow and glaciers

___________

 

Other Glacier Retreat Effects: Natural Hazards

-Hazards pose a threat to human life and livelihoods and can cause damage to infrastructure and industry.

-floods

-avalanches

-mudflows

-icebergs

 

Kolka Glacier Disaster… (Russia)

-sept 2002, glacier broke off and slid down valley

-caused avalance and mudflos

-overran Karmadon village 18km downstream

->120 ppl killed

 

Regions where glacier hazards are currently problematic:

-BC

-Iceland

-Alps

-Andes

-Caucasus mountains

Ice Sheets

“The greatest climate change threat for humans lies in the potential destabilization of  the Greenland and Antarctic Ice Sheets” (NASA)

 

Sea Rise Contributions (possible)

-Antarctic: 60m

-Greenland: 7m

-Other Glaciers: 0.5m

-This century, prob 1m rise (50% glacier)

-possible 4-6m

 

-Greenland influences the THERMOHALINE ocean circulation (cold water and salt water both sink)

Melting Permafrost
Permafrost affects infrastructure, ecosystems, leaks water to the oceans, and frees methane
Pollution and Disturbance in th Arctic

On 25 Dec 2008, 100 000 gallons of oil-ater mix escaped a corroded water-injection popeline at Kuparuk

 

The Arctic tundra ecosystem is extremely sensitive to pollution and disturbance*

-poor soils and harsh climate leave little margin for tundra systems to restore themselves

-damage from erosion persists for centuries, and the extinction of any species affects many others.

 

Petroleum infrastructure in the North is fairly extensive, and severly afectts caribou habitat disturbance

(caribou density inversely correlated with road density)

Nanook of the North

Write down all the ways in which traditional knowledge depicted in this movie is threatened by environmental change.

 

Fragment 1: Intro part 2: http://www.youtube.com/watch?v=9wmHvkrhmII
Fragment 2: First episode: www.youtube.com/watch?v=cLERFRQl5EY

Environmental Change in Northern Ungava

-mining, tourism, trade, industrial activity

-climate change

-sea level change

-ecological change

-pollution, alcohol

-politics (Ungava now a part of QC)

 

POSSIBLE Effects due to changes:

-materials

-TK

-landscape

-population health

-people’s self-esteem and dignity

;

socio-economic cultural, and psychological effects

Cultural Changes

-Globalization

-changing economics and food sources

-mixed cultures

-technological and educational adjustments

-obsolescence of annual calendars of innuit/other groups

-tourism and consumer tourism and ecotourism

Sources of socio-economic resilience and vulnerability that characterize arctic systems

SOCIAL AND INSTITUTIONAL PROPERTIES

source of resilience

-sharing of resources and risks across kinship networks

-multiple jobs and job skills held by an individual

source of vulnerability

inadequate educational infrastructure to plan for future change

-relatively unskilled labour force

opportunities for adaptation

learning and innovation fostered by high cultural diversity

;

ECONOMIC PROPERTIES

source of resiliance

-flexibility to adjust to change in mixed wage-subsistence economy

source of vulnerability

-decoupling of incentives driving climatic change from economic consequences

-non-diverse extractive economy: boom-bust cycles

-infrastructure and political barriers to relocation in response to climate change

opportunity for adaptation

-substitution of local resources for expensive imports (food, fuel)

-national wealth sufficient to invest in adaptation

Chapter 1 Main Themes (7)

1. Global envionmental changes can be systematic and cumulative

;

2.Linear vs Non-Linear Response

;

3.Feedback Mechanisms (pos + neg)

;

4.System response: storage – lagged response – catastrophic events

-this is why landscapes are always in “inclomplete transition” and “readjustment”

;

5.Scales of systems: spatial and temporal

;

6.Temporal and spatial variability: worldwide trend does not equal local trend.

;

7. Instabilities in systems and “tipping points”

Hydrologic Cycle

Earth is the “blue planet”

-Satellite imagery changed the view of scale of processes and interconnectivity

;

Typical Conditions on earth:

Pressure: 1atm (101kPa)

Temperature: -89 to 58C

;

Whether water is liquid, solid, or ice depends on Pressure and Temperature. The “triple point” is where they meet.

;

RETENTION TIMES (Hydro Cycle)

-Biospheric/atmospheric/river water = 1-2 week

-ice caps/glaceris = ~1000 years

-oceans and seas = ~ 4000 years

-Groundwater = ~2weeks – 18000 years

Cryosphere response and archaeology

Changes in the components of the cryosphere occur at different time scales, depending on their dynamic and thermodynamic characteristics

-frozen ground = biggest temporal range

-ice sheets longest time scale

-snow/river/lake/sea ice = shortest time scale

-glaciers and ice caps in between

;

Human response times= seeing is believing… though many systems are so complex that it is hard to measure the systemic changes, let alone see them.

;

Otzi = the prehistoric iceman, found 1991, 5200 years old

;

10400 year old hunting weapon found in Melting Ice Patch in 2007.. organic material is preserved in snow and ice!!

Back to the future…

1958 http://www.youtube.com/watch?v=0lgzz-L7GFg
Excerpt from the educational documentary “Unchained Goddess” produced by Frank Capra for Bell Labs for their television program “The Bell Telephone Hour.”

________

1989
http://archives.cbc.ca/environment/climate_change/clips/14650/
The Arctic: ‘first and worst’ for global warming. CBC News 12 Oct 1989

______

2009 http://www.ted.com/talks/james_balog_time_lapse_proof_of_extreme_ice_loss.html
Glacier talk and time- lapse photography footage by James Balog, professional photographer, July 2009.

Tipping Points

Many complex systems have critical thresholds (tipping points) at which the system shifts abruptly from one state to another.

;

ie. asthma, market crashes, climate, etc

;

“13th tipping point” – the shift in human perception from personal denial to personal responsibility?

;

** look up some common cryospheric tipping points

Radiative forcing factors (7)

1. orbital cariations (tilt, eccentricity, etc)

2.solar energy variations

3.land-ocean distribution (plate tectonics)

4.orography (mtns)

5.ocean currents

6.surface reflecting properties (albedo)

7.atmospheric composition (gases, volcanoes, fires)

Components of the climate change process

Natural and human influences influence direct and indirect changes in climate drivers, which impacts radiative forcing and non-initial-radiative effects, which result in climate perturbation and response, which can result in biogeochemical feedback processes.

;

The Keeling Curve

-Mauna Loa observatory in Hawaii

-CO2 concentrations in atmosphere have increase linearly since 1960 from ~310ppm to almost 400ppm (low variation… seasonal fluctuations very evident).

-Natural range in the last 10kyrs has been 260-280ppm.

;

RELATIONS OF DIF TIME SCALES OF CLIMATIC CHANGE TO CRYOSPHERIC COMPONENTS

10k-100kyrs = ice sheets

1k-10kyrs = ice caps, ice fields, large valley glaciers

100-1000yrs = small valley glaciers

10-100yrs = cirque glaciers

1-10yrs =; neves, snow fields

Ice sheet, permafrost, and sea ice changes in response to climate change

Greenland is meting at an alarming rate.

In some places, this increased meltwater results in a dramatic increase in ice flow, and related iceberg discharge.

Rates of surface elevation change derived from laster altimeter measruements at over 16000 locations on the Greenland Ice Sheet indicate rapid thinning in many regions. Mass balance is estimated to be decreasing quickly.

;

Antarctic shows mixed trends, with thickening in some regions and thinning in others.

;

Permafrost – Permafrost zones occupy up to 24% of the exposed land area of the NH.

;

Trends in permafrost temperatures in N Alaska over last ~25 years are increasing. There has been a general increase in permafrost temperatures in N Hem over last several decades

;

Sea Ice extent is decreasing rapidly

;

Freeze-Up and Breakup dates from norther lakes and rivers are also changing in response to climate change

Antarctic Tourism Changes

Tourism activities are epanding tremendously with the number of shipborne tourists increasing by 430% in 14 years and land-based tourists by 757% in 10 years.

;

Antarctic annual sea-ice extent is projected to decrease by 25% by 2100. This means easier access to the Antarctic continent by ship.

This is likely to affect not only research, which is a main activity in a continent designated as a “natural reserve devoted to peace and science”, but also commercial activities, such as tourism.

Antarctica and measuring

-98% of antarctica is ice covered

-70% of Earth’s freshwater is in teh Antarctic Ice

-91% of earth’s ice is in Antarctica

-average thickness=2.3km/ max=4.8km

;

*It is the highest, driest, windiest, and coldest continent

-it hasn’t rained at Canada glacier for at least 2million years

-can be down to -88C

 

MEASURING ANTARCTICA

-www.youtube.com/watch?v=w4x5-QVRb7M

 

In mid 2000, Pine Island Glacier formed a large crack in its ice shelf, which expanded 15m/day.

In 2001, 7yrs of glacier outflow releaesed to the sea in a single event

Measuring and Data

Measurements

-the process of measuring

-the quantities coming directly from these measurement processes

 

Observations

-receiving knowledge of the outisde world through the senses, or through the recording of data using scientific instruments (=measuring)

 

In Situ measurements/obervations

-usually obtained through direct contact with the respective subject

-may be precise, accurate and representative of site-specific location, but not necessarily of a larger region

 

Data

-quantification to represent geophysical state variables and with that the state or change of processes or systems

 

CRYSOPHERE

There are currently efforts to both standardize/collect/distribute data (UN Global Observation Systems, World Meteorological Organization) as well as to centralise, catalogue, and distribute past/present data (World Data Centres, World Glacier Inventory, etc)

Climate proxies

-ice cores

-tree rings

-boreholes

-corals

-lake/ocean sediments

-pollen

AWS in Antarctica

Automatic Weather Stations

 

First weather observations mid-late 1800s

 

Detailed climate observations >1950s

Palynology techniques example

1. count and identify 200 pollen grains/sample

 

2. Divide census into three parts

-arboreal pollen (AP)

-non-arboreal pollen (NAP)

-spores

 

3.express results as % of total AP at that particular depth

 

4. Plant assemblage at a particular horizon — pollen spectrum

 

5. Curves from a series of stratigraphic positions — pollen diagram

 

6.age dates are determined by 14C dating and cross-dating

 

7.History of vegetation change linked to climate, environment, and anthropological influences

 

 

Snow Measurements

MAIN: snow Extent, Thickness, and Density

 

Additionally: Snowpit analysis for:

-avalanche forecasting

-recording of snow accumulation in glacier mass balance studies

-assessment of snow variability

-assessment of spring runoff

 

SNOW PIT

1.dig pit

2.record layer stratigraphy

3.measure resistance

4.measure hardness

5.record size and shape/form of snow crystals

6.record snow density

7.record snow temperature

8. record snow stability (shovel compression test)

 

equipment…

-shovel, tape, ruler, fieldbook, pencil, knife, thermometer, magnifying loupe, snow crystal card, density kit

 

SNOW PILLOW & SNOWTEL STATIONS

www.youtube.com/watch?v=tlE8SDqW2Ow

-lots of snowpillows in BC and Rockies

River freeze-up and break-up in the arctic

www.youtube.com/watch?v=0PMGDJULjwg&feature=related

 

Torne River, Kiruna, Sweden, 2004

Sea Ice Depth and Extent

Can measure:

-extent

-concentration

-ice type

-thickness

 

In Situ Ground measurements

www.youtube.com/watch?v=L3Ku5Oi188s

 

In situ submarine measurements

 

Satellite measurements

AMSR-E = concentration or drift

ICESat = thickness

 

-with multiple sensors, can get sea-ice area flux and thickness, which can together give you sea-ice volume flux

 

Ice thickness with satellites can be calculated from freeboard height, assuming hydrostatic balance and using in-situ and satellite snow depth data

Lichen as a proxy for ice retreat observations

Lichen = algae + fungus

 

Algae = photosynthesis = good for lichen

Fungus = shelters algae in greenhouse

Cemetary grave stones have exact dates, from which you can get lichen growth curves

 

Rhizocarpon geographicum

-Most commonly used

-growth 1-4mm/yr

 

Compare calibrated lichen size with lichen size in geological terrain

 

**Lichen growth rates vary with elevation, proximity to sea, aspect, and rock type

-max is 5000 yrs before present

 

R. geographicum does now like carbonate rocks, but needs silicate rocks

Scientific Revolution in the last 30 years

Geophysical methods (GPS, RES, Seismic, Gravity)

 

RS

 

Ice coring and analysis

 

Computer modelling

AWS

 

Dating methods

Impurities in Polar Ice and their Sources

Sea Salt (Na+, Cl-, Mg++, SO4-, K+) – oceans

 

Terrestrial Salt (Mg++, Ca++, CO3-, SO4-) – continents and continental shelves

 

Tephra and gasses (H+, sulphate, nitrate, shards – ash layers) – volcanic eruptions

 

Biological Gases (H+, NH4+, NO3-, SO4-, CH2, SO3-, F-, HCOO-, organic compounds) – biological/anthopogenic gas emissions

 

Cosmogenic radionucleides (10Be, 36Cl, 14C) – interaction cosmic rays and atoms (solar activity and geomagnetic field)

Nitrate and Sulphate in Ice Cores

-both gradually increasing since 1900s due to coal combustion industrial revolution

-both now well above 2000 year averages

 

-some sulphate peaks related to volcanic eruptions

 

US Clean AIr Act 1972 resulted in huge decrease in sulphates

 

 

Problem with gas dating in ice is that there is mixing between layers!!

EPICA DOME C

longest continuous climate record

 

Preliminary results:

 

-Over the last 740kyr, earth experienced 8 glacial periods and 8 interglacial

 

-In the last 400k yrs, warm periods had temperatures similar to todays, before that, warm periods were cooler, but lasted longer

 

Cooling is gradual, warming can be abrupt

 

Concentrations of sodium, sulphate, and dust are way higher during glacial periods

 

Concentrations of methane, carbon dioxide, are way higher during interglacial

 

CH4 residence time = 10yrs

 

CO2 res is over 100yrs… globally well mixed

Younger Dryas and Little Ice Age

The Younger Dryas stadial, also referred to as the Big Freeze,[1] was a geologically brief (1,300 ± 70 years) cold climate period between approximately 12,800 and 11,500 years ago (between 10,800 and 9,500 BC).[2]

 

The Little Ice Age (LIA) was a period of cooling that occurred after the Medieval Warm Period. While not a true ice age, the term was introduced into scientific literature by François E. Matthes in 1939.[1] It is conventionally defined as a period extending from the 16th to the 19th centuries

stadials and interstadials

periods of warm and cold within an interglacial

 

Younger Dryas was a stadial

CO2 and ice cores

Relationship b/w CO2 and Temperature is not linear!!!

 

CO2 max 290ppm in the last 650000 years until the most recent increase , which is unequivocally due to human activities

 

CO2 accounts for only ~1/3 of the total temperature increase in teh past

 

CO2 is amplifier of climate (dtrigger is most often orbital or ocean oscillations)

Dust and and Na Ice cores

-We get more dust during cold periods due to more wind, less vegetation, more fines available through erosion and lower sea levels.

 

~1400, got really cold, and sodium levels increased due to colder seas. Wiped out Vikings.

 

PSAs (potential source areas) for Antarctica during glacial periods are NZ, Dry Valleys, and South America

 

Corroborating evidence:

-size of source area

-volcanic eruptions (tephra)

-other chemicals and isotopes

-LGM atmospheric circulation models

Insolation

10Be concentration (relative to the mean value) at South Pole is a measure of solar insolation

 

Thames Frost Fairs (1608-1814).. longest and coldest in 1683 (3 months)- London

 

THE MILANKOVITCH CYCLE

Insolation co-trigger of clmiate change at longer timescales

 

Precession + Obliquity + Eccentricity + Solar Forcing combine to form “Stages of Glaciation”

 

The cycles match gvery well to temperature in Antarctic ice cores, apart from recently the cycle has gone down, but the temperature has not.

Major findings from ice cores drilled in the Greenland and Antarctic Ice Sheets (9)

1. Close correlation b/w climate and GHG conc.

 

2.Ice ages are dustier, and storm tracks change

 

3. Some atmospheric chemistry is regional (methane)

 

4. Anthropogenic influences on atmosphere are global (nuke tests, emissions)

 

5.Some climate oscillations are global, other confined to N Hem

 

6.Coupling of timing and magnitude of global climate changes between the 2 hemispheres

 

7.Rapid and large oscillations during the last glacial period and the end of the last transition (start Holocene)

 

8. Climatic stability of the last 10k years contrasts with extreme climate variability through most of the rest of the last glacial

 

9. Last interglacial (125kyBP) was 2-5C warmer than present (orbital forcing)

Stefan-Boltzmann Law and Wien’s Displacement Law

Stefan-Boltzmann Law

As the temperature of an object increases, more radiation is emitted each second.

;

Wien’s Displacement Law

As the temperature of a body increases, so does the proportion of shorter wavelengts

 

From these two laws it follows that:

 

Sun’s radiated emission very high and mostly in the form of shortwave (SW) radiation.

;

Earth’s emission low and mostly longwave (LW) radiation

 

Net heat transport is from the tropics to the poles. Greater outgoing radiation at the poles relative to incomming.

Radiative Forcing

Contribution of RF associated with anthropogenic GHG emissions: ~2.6W/m2 since 1750.

-mostly CO2 and CH4

 

Combined anthropogenic RF: ~2.6W/m2 since 1750

-inclued atmospheric aerosols (direct effect and cloud albedo effect)

Surface energy balance at a point

Q= Fsol(1-alpha)+FIR+FSE+FLE+Fcond

 

Fsol = incoming solar shortwave radiation

 

FIR = upwards and downward radiation flux at surface (Stefan Boltzman law)

 

FSE & FLE = sensible and latent heat fluxes

 

Fcond = conduction flux for ground/ice/snow/ocean surfaces (Fourier’s law)

;

Fgeo = geothermal heat flux

;

ENERGY BALANCE OVER POLAR TERRAIN

Closed Forest and Coastal Tundra and Thick Sea Ice: large net income in summer, small net outgoing in winter

Glacial Ablation Zone: net incoming in summer, no data for winter

Antarctic Coast: Small incoming in summer, small (about the same) outgoing in winter

Thin sea ice (winter only) net is outgoing, most incoming comes from ocean.

;

;

Properties of the Cryosphere influencing surface energy balance

SNOW AND ICE
-large albedo: reflect large part of incoming energy

-store and release latent heat: affect the sasonal cycle of the surface temperature

-Good insulators – reduce the heat loss from underlying surface (land or ocean) (largest effect in winter)

;

SEA ICE

Sea ice restricts heat and gas exchange between ocean and atmosphere

-When sea ice forms, only a fraction of the salt present in the ocean is trapped in the ice, the remainder is ejected towards the ocean (brine rejection)

;

PERMAFROST

-patterned ground – albedo and surface roughness

-melt – sea level

Cryospheric Feedbacks

SNOW AND ICE

-snow-ice-albedo feedback

;

SEA ICE

-sea ice-albedo-polynia feedback

;

PERMAFROST

-Melt-GHG release feedback

Heat Properties of Ice and Snow

Latent Heat of Fusion of Ice

-amount of energy required to transform ice to water at the melting point

=3.35*10^5 J/kg

;

Specific Heat

-heat energy required to increase the temperature of a unit quantity of a material one degree (C or K)

;

Water Vapour (100C) = 2.08 J/gK

Water liquid (25C) = 4.18 J/gK

Ice (-10C) = 2.05 J/gK

;

Bedrock specific heat capacity is only ~0.2 J/gK

;

So what is the effect of snow/ice cover on the earth’s energy budget given the above properties?

Effect of temporal variability of Snow Cover

SNOW COVER VARIES SPATIALLY AND TEMPORALLY!

 

Bowen ratio:

The ratio of sensible heat and latent heat energy fluxes from one medium to another

B=Qh/Qe

… and is related to the evaporative fraction

Snow Measurements

SNOW MEASUREMENTS
Main:

-snow extent

-thickness

-density

 

Also, snow pit analysis for:

-avalanche forecasting

-recording of snow accumulation in glacier mass balance studies

-assessment of snow variability

-assessment of spring runoff (SWE)

 

 

SNOW COVER CHARACTERISTICS

Thickness and Stratification

=F (snowfall, wind redistribution, T, forest cover, terrain)

 

Densification and settling

 

Metamorphosis

-snopack T gradient->dry snow metamorphosis

-Rounding and enlarging of crystals -> wet snow metamorphosis

Crystal Type/Size

-Before and after metamorphosis

T Gradient

-Critical instability when >1C/10cm

Inside the snowpack…

-Temperature at the base is 0C

-Cold air wave penetrates into top of snowpack

-Surface is usually relatively warm, it gets colder, and then gradually warmer again with depth

 

Average temperature gradients in a snowpack over 10cm are approximately -0.1 to -0.6  degrees. However, these fluctuate more at higher elevations

 

Thinning of layers due to settlement and metamorphosis occurs mainly in the first 3 weeks and after new snowfall

 

SNOW STABILITY

-can be tested using the shovel compression test

-trying to find regions of fractures and weak layers

-look at failure depth vs failure force graphs to determine danger

 

Can also use the Rutschblock stability test

-cut a block 2mx1.5m and jump on it with skis

 

Conducinve to Avalanches:

-Layer of platy or round crystals

-large T gradient

-Large density gradient

-suddent air temp changes, considerable snowfall, wind

-depth hoar is dangerous

Snowfall Modelling

Empirically-derived Function

-local

 

Degree Day Model

-crude

 

Multiple Regression

-Need measurements and longitudinal time series

Microbial Life In Snow and Ice

‘Watermelon Snow’ – Chlamydomonas nivalis

 

Lives in subglacial ecosystem

-specific surface glacier ice conditions

-results in blood falls

-source area rich in iron, high chloride, salinity, and sulfate

 

____

 

Very recent research has found microbial life in subglacial lakes

-Can use RADARSAT remote sensing to identify locations of underwater lakes

 

LAKE VOSTEK

Discovered in 1996 from decades of seismic studies, radar surveys, and satellite imaging “one of the last unexplored frontiers of our planet”

 

Lake Vostok is the biological equivalent of the Heisenberg uncertainty principle (how do you sample something without changing it?)

 

Instead of drilling into the lake, they drilled into the accreted ice zone, which was recently frozen and contains preserved, contemporary speciments

 

Names of new species:

 porpoise, thanksgiving leftovers, sphere

Remote Sensing of the Cryosphere

Sea ice, Glaciers, Ice-sheets, Snow cover

-Remote, large, changing areas

 

 

Monitoring of:

-status

-changes

-process studies (understanding)

-verification of models

-early warnings

-predictions

 

MODIS true color image was used to identify Antarctica’s B-15A iceberg

-also, other huge ice bergs which have broken off

RS of snow cover (what, why?)

WHAT

-surface albedo

-thickness

-water content

-melt onset

;

WHY?

-surface energy balance

-glacier mass balance

-water availability (runoff, flooding, water management)

-climate change

Which satellites are used for which studies?

Spectrum determines which spectral bands suitable for certain studies

;

Resolution determines smallest unit that you can capture

;

Revisit and size of image determines how often (days) you have coverage of target

;

Ground coverage determined how far N or S the images reach (usually poles not covered)

;

Snow and ice have varying spectral reflectance curves

-it is totally different for melting snow and fresh snow

;

Spectral reflectance is not static, but dynamic!!

;

Effects changes in the Snow/ice:

-impurities visible spectrum

-Grain size: near and middle IR

-Liquid Water: increases effective grain size

-Density: independent

;

ASTER has more spectral bands in the areas we would want to use (for snow), yet resolution is variable (at high wavelength, resolution is worse, in visible, it is better)

;

Different Satellites have different Ranges/#bands,Resolution, and Return

;

Aster: 520-12400/14/15-90/;16

Modis: 405-14385/36/250-1000/;3

Landsat7: 450-12500/7+PAN/30-60/;16

AHRR: 580-12400/6/1100-4000/0.5

SPOT: 500-1750/4+PAN/10-20/;3

GOES-8: 520-12500/5/1000-4000/15min

;

SMMR

SSM/I (microwave)

SAR (radar)

Procedure to convert satellite data to albedo

1) Take raw data numbers (DN-0-255) and convert to spectral refectance (L;)

-For DN=0 and DN=255, the L; is known from the satellite characteristics (metadata)

-linear interpolation to find L; values for the rest of the DN values

;

2)Atmospheric correction by ‘radiative transfer models’

;

3)Anisotropy corrections

;

4) Narrowband to broadband extrapolation (entire spectrum)

MODIS

Moderate Resolution Imaging Spectroradiometer

;

Onboard Terra Satellite

Res: 500m and 0.05deg (~5.6km)

36 bands

Return 1-2days

;

MEASURE:

-global vegetation

-land surface changes

-albedo

-temperature

-snow and ice cover

;

Has automated snow-mapping algorithms!

Use:

-band 4/6 (normalised difference snow index: NDSI)

-band 1/2 (normalised difference vegetation index: NDVI)

-band 2

;

NDSI= (MODIS band 4- MODIS band 6)/

(Modis band 4 + Modis band 6)

;

;NDSI ;0.4 is snow

Reflectance in band 2 should be greater than 11$

Band 6 stays high for clouds

;

If NDVI maps forest, then map snow for NDSI ;0.4 as well.

Reflectance in Band 4 should then be ;10% in the forest

;

MODIS has determined that N America’s max snow cover occurs Jan17-24 on average

 

PROBLEMS

-Atmospheric corrections -> algorithms

-Grid Size -> sub pixel snow

-Darkness -> need passive microwave

-Albedo -> narrowband to broadband reflectance

-> anisotropy (need bidirectional reflectance correction)

 

Clouds -> obscuring or ‘false’ snow (due to ice in high clouds: Summer)

Errors of Omission -> snow free – snow – cloud – snow melted

 

-need to use algorithm to remove cloud from snow

 

Sometimes, snow cover can be >50% of N-Hemisphere land surface

-Rivers help to determine whether snow or cloud

 

Darkness is a problem for visual spectrum not a problem for radar)

Microwave Satellites

Can determine snow depths and SWE

-Volume scattering by snow reduces the microwave radiation from the underlying ground

There are active and passive microwave sensors

 

Microwave satellite sensors are not susceptible to atmospheric scattering

-active = imaging (strength backscatter signal, ie radar)

-passive is non imaging (altimeters, scatterometers)

 

Microwave wavelengths from ~75mm-0.1m

Somewhere in the middle is used for microwave ovens

 

RADAR

-measures strength and round-trip time of microwave signals emitted by a radar antenna and reflected off a target (distance surface or object)

 

-radar uses: microwave wavelengths (1cm-1m) and polarizations (waves polarized in a vert or horiz plane)

 

-Earth’s surface scatters the energy in the radar pulse (some reflected back to antenna = backscatter)

;

Antenna receives backscatter as a weaker radar echo in a specific polarization (hor/vert, not necessarily the same as the transmitted pulse)

;

-Echoes converted to digital data

;

-Radar pulse travels at the speed of light -; easy to calculate roundtrip time of a pulse to calculate the distance or ‘range’ to the reflecting point.

;

****Backscatter is a function of electrical(absorption/transmittance) and gometrical (surface roughness) surface properties

;

***Ice roughness, water content, stratification, etc picked up by radar but not by optical photograph

GLACIER AND SNOW SURFACE DIELECTRIC PROPERTIES

;

Liquid water -; absorbs microwave energy

-low backscatter when liquid ;1%

Liquid Water -; influences microwave penetration

-wet snow/ice – backscatter from top cms -; surface scatter

-dry snow pack – backscatter from tens of m -; volumetric scatter

;

Backscatter also f(stratigraphy causing dielectric contrast of different layers)

-snow -; backscatter controlled by changing snow grain size due to ago

-layers with a dielectric contrast (ie. dy snow/firn interface)

;

COMPLICATED and sometimes CUMULATIVE EFFECTS

-Melting areas = liquid water = low backscatter

;

-Dry homogeneous snow pack ;20m depth = low backscatter (little dielectric contrast)

;

-Dry inhomogeneous snow pack (grain size changes) -; relatively high backscatter

;

-Firn overlain by dry snow -; rel high backscatter from interface of snow/firn layers

;

-Percolation or superimposed ice zone with ice lenses -; high backscatter if no active melting

;

-Active slush zone -; low backscatter: liquid water

;

-Dry ice -; low if not rough

;

***Sh= surface height variations

-surface is considered smooth or rough (proportional to wavelength and incident angle)

;

Radar can be used to detect snowline on a glacier!

Radar Error Estimates

Based on comparison with ground measurements and image comparison

;

Snow cover area:

Modis, AVHRR, GOES-8, etc 5-10%

Passive microwave ;1%

;

SWE

SAR and AMM/I large errors with point measurments, but ‘only’ 10-20mm w.e. when area averaged

GLIMS

Global Land Ice Measurements From Space

;

-GLIMS is an international consortium (26 nations)

-Primary goal: to determine the extent of the world’s glaciers and the rate at which they are changing

 

HOW?

1)acquire a global set of multispectral, stereo satellite images of the world’s land ice near the peak or end of the melt season

2)map the global extent of land ice

3)analyze a representative selection of glaciers for length, area, ice flow, snowlines, and interannual changes in these

4)Build and populate a publicly accessible digital database of te world’s glaciers

 

Principal observing instrument: ASTER (aboard NASA’s Terra satellite)

-supplemented by others (LANDSAT, Ikonos, etc)

;

Consortium has 23 regional centers

ASTER

-used mainly by GLIMS

;

APPLICATIONS

-terrain classification

-DEMs

-Glacier motion

-glacier monitoring

-geomorphological and terrain changes

-lakes

-glacier hazards

-GLIMSView

;

ASTER Global DEM (GDEM)

-released June 2009

-Free of charge for everyone

-30 m resolution world-wide coverage

;

Was used at James Ross and Vega Islands

-Antarctic Peninsula

-monitored a retreat of 42.4km2

-loss of ~4 glacier cover

-mostly floating ice melted

-retreat rate doubled from 75-88 to 88-01

Can calculate ice velocities, lake growth

;

Hester did a GLIMS study “Glacier rereat and sensitivity related project”

-Clemenceau Ice Field Group (CIG) and Chaba Icefield (CH)

-In the area, 12 of 21 glaciers have significantly accelerated retreat rate for 1985-2001

;

Changing landscape terminology

Slope Movement:

-Gelifluction

-Rockfall vs rockslies

-Landslides and mudslides

;

Glacial Lake Outburst Floods (GLOFs)

;

Permafrost:

-patterned ground

-pingos

-thermokarst

Permafrost Landforms

READ ABOUT ALL OF THESE FEATURES!!

;

Cryoturbation (cryosols or gelisols)

;

Ice/Frost wedge polygons

-faulting

;

Hummocks

;

(non)sorted stone circles, polygons and stripes

-polygons can be low-centred or high-centred

;

Alases (large thermokarst depressions)

;

Palsas (frost heave of peaty ground /w ice lenses)

;

Pingos (hydrolaccolith: a hill of earth-covered ice)

-can be open or closed system, or collapsed (dead pingo)

;

**much of the paleo-process information is from studying sediments (and stratigraphy of sedimentary units), rather than from landforms

;

High-latitude areas on Mars and Earth both exhibit patterned ground where shallow fracturing has drawn polygons on the surface

Permafrost

Continuous vs Discontinuous coverage

cont: over 90% region covered

dis: 10-90%

;

Permafrost is frozen ground

Periglacial environment

;

***Continuous permafrost zone coincides approximately with the 10C isotherm

~74N

;

Present landcover ;20%

-at LGM ~40%

Blockfields

Blockfields are a periglacial landform

Blockfields = felsenmeer = blockmeer= stone fields

;

Large, sheet-like expanses of weathered blocks (over .25m in size)

-Usually cover bedrock, though not necessarily same type of rock

-low surface gradients

-found in former arctic or alpine regions

;

No rock debris source (such as cliff) is seen, but the slope may rise to a ridge crest.

;

The block in blockfields are usually angular and are often thought to be the result of ‘mechanical’ weathering processes

;

www.youtube.com/watch?v=jyWejbOV7co

Blockfields sometimes survive subglacially

-can survive under cold-based ice sheets

Arctic Ecozone Classification

Arctic ecozones based on the mean temperature of the warmest month

;

Arctic/Polar

;2C = Polar desert

2-6C = Northern Tundra

;

Subarctic/Subpolar

6-10C = Southern Tundra

;10C = Forest tundra to Boreal forest zone

;

Boreal Forest = Taiga = Swamp Forest

-Norther Boreal forest in Canada vegetation:

-Black Spruce (P. Mariana)

-White Spruce (P. glauca)

-very low biodiversity

-Black spruce adapted to slightly colder than White spruce, but not by much

Treeline

Species are monitored in N America and EuroSiberia

;

Position of summer and winter arctic front in relation to the polar treeline/the southern boundary of the boreal forest in North America (they correlate strongly)

-polar fron in summer and winter boundaries basically outline the boreal zone

;

Arctic Front=

1)semipermanent, semi-continuous front b/w the deep, cold arctic air and the shallower, ess cold olar air of northern latitudes

2) Southern boundary of the Arctic air mass

;

TREELINE MIGRATION

Difficult to measure:

1)highest tree (or farthest North) often not found

2) Present treeline inaccurate

3) Present treeline not in equilibrium with present climate

;

Asymmetric response to climate forcing:

-Northward (or up-mountain) migration of treeline much more rapid than southward (down-slope) migration

;

Established trees might survive for a while in deteriorated climate, but new trees will not establish in such a climate

;

Alpine treelines were ;200m higher than at present during Hypsithermal (6-3.5kyBP)

Degradation of cryospheric landforms

Permafrost is melting

-affects infrastructure and ecosystems

-leaks water to the oceans and frees methane

-www.youtube.com/watch?v=vSLHvZnbYwc

*top 3m of arctic permafrost may be gone by 2100

;

Dried mudflows occur along slopes especially in spring, when the uppermost layer of permafrost melts;

Mudflows consist of sediment saturated with water and can have speeds ;100km/h

;

Bodies melting out of permafrost may contain smallpox virus (Science) as it is resilient to freezing

;

www.youtube.com/watch?v=31aOYcGo-sg

;

PINGO DEGRREDATION

-is happening (look up)

Cryospheric Natural Hazards

Hazards pose a threat to human life and livelihoods and can cause damage to infrastructure and industry

-Floods

-Avalanches

-Mudflows

-Icebergs

;

*Look at hazard glacier regions map on review lecture*

;

GLOFS

-In the Himalayas, the frequency of GLOFs has increased in the 2nd half of the 20th century

-At present ; 200 lakes pose a flood hazard in Hindu Kush-Himalayan region alone

The Dig Tsho GLOF (1985) killed 5 people, destroyed the Namche small hydropower project (~US 1.5million), 30 houses, 14 bridges, and cultivated land.

The BEAT THE GLOF ACTION RUN runners gather at Imja Lake (5010m), the fastest growing glacial lake in the Himalayas

-It is growing at 74m in length annually as the glacier behind it melts away

;

KOLKA GLACIER DISASTER, RUSSIAN CAUCASUS

Sept2002

-glacial broke off and slid down valley

-caused avalanche and mudflows

-overran Karmadon village 18km downstream

-over 120 ppl killed

;

__

Some research suggests that landslides are on the increase due to climate change.

But is this also the case for rockfall and large rockslides? (See Hester’s Study)

Large Rockslides: Case Study- Tsar Mountain

STUDY OBJECTIVES

-Is this rockslide typical for long-runout rockslides on glaciers?

-What are possible triggers?

-What are the effects of the rockslide on the glacier regime?

-Can climate and seismic data constrain the timing of rockslides in this region?

-What is the contribution of events like these to the overall sediment budget and denudation rates in alpine regions?

 

METHODOLOGY

Imagery

-Landsat7, ASTER, SPOT quicklooks, Astronaut photography, Airborne photography from helicopter

 

Seismic Data

-4 seismic stations (Earthquake Canada)

 

Weather Data

-2 automatic snow pillow stations (BC Ministry of Environment)

-1 climate station (Environment Canada)

 

Glacier Data

-imagery

-field measurements on Shackleton Glacier (8km NE)

______

 

Study of Cirque glacier rockslide (2.2km long)

-fall of 311m

-length of rockslide runout depends on substrate

 

RHETORICAL CONTROVERSY?

Rockslides on glaciers have longer runout because

-lower friction with bed?

-confined flow by valley walls and moraines?

-entrainment of snow/ice in the fockslide base: fluidization?

 

POSSIBLE EFFECTS OF THE ROCKSLIDE ON THE GLACIER

1)albedo effect

2)increase/decrease of sensible heat flux

3)increase in basal shear stress by increase apparent ice thickness

4)hydrological effect by sudden impact

5)alteration of the supraglacial drainage

6)snow/ice incorporation during fluidization

 

TIMING ROCKSLIDE

-sat images bracken b/w 26 Aug and 23 Sept

-weather data suggest 10-15 sept (huge precip and temperature variation)

-seismic data pinpoints it to 14 sept 2000

-for seismic data, had to differentiate b/w earthquakes and surface events

-can do this with shape of seismograph

 

CONCLUSIONS

The Rockslide

-is similar to other rockslides on glaciers

-stress fatigue in combination with intense rain (~30mm/day) and snowmelt around freezing T co-triggered the rockslide

-caused a 0.2-0.4 m w.e./a reduction of ablation (7-12%) and had some hdrological effects on glacier

 

SEISMIC EVENTS
-since 1985: 26 significant seismic events <40km of the cirque: none large enough to trigger rockslides

-Seismic waveforms and frequency spectra -> no unequivolcal evidence for seismic tremors caused by rockslides

Paraglacial Terminology

Landscapes in transition

Palimpsest

 

Proglacial

Periglacial

Paraglacial environment

Paraglacial period

 

Reinterpretation of landforms, sediments and stratigraphy

Sediment exhaustion curves

 

___

 

The ‘paraglacial period’ is the period of readjustment from a glacial to a nonglacial condition, as fluvial, slope and aeolian systems relax towards a nonglacial state

 

At the scale of the Pleistocene land ice, this paraglacial period occurred between 12-6kyBP

 

At the smaller, alpine glacier retreat scale, we are still in the middle of it.

Geomorphological and System theories

Hutton (1880s): geological cycle

 

Church (1970s): paraglacial

 

Hewitt (1990s): landscapes of transition

 

Brunsden (1990): system stability

 

Holling: relisience (1973) & Panarchy (2002)

 

Diamond’s (2005) collapse of societies

Landscape System stability and sensitivity

Hutton’s rock cycle (decay of continents to the sea and then to uplift again) = Uniformitarianism

 

BUT:

-landscape changes are through punctuated equilibrium…

 

Is equilibrium a state of stability or conservation???

 

stability: the temporal behaviour of a landscape over time

sensitivity: is the susceptibility of landforms to change

 

Phillips (2009) framework for the assessment of geomorphic changes and responses based on 4Rs

-Response (reaction and relaxation times)

-Resistance (relative to the drivers of change)

-Resilience (this is how well you maintain a self-organizing capacity? -> recovery ability, based on dynamical stability)

-Recursion (positive and/or negative feedbacks

 

resilience = capacity to dal with change and contiue to develop. Ecosystem resilience, social resilience, etc.

Panarchy

Holling’s panarchy cycle incorporates collapse and creative reorganisation as two of the NORMAL stages of an adaptive cycle

;

2-Phase Adaptive Cycle

Phase 1: expansion and prosperity with growth and accumulation of capital and wealth. Though changes may be slow, the effects can become substantial as they gradually accumulate.

;

Phase 2: “back-loop” characterized by creative destruction and reorganization, potentially suddenly. Period of low predictability (potential for surprises). Suddenevents (eg. forest fire), can unexpectedly and sometimes irreversibly “flip” an ecosystem or economy into a qualitatively different state by triggering the release of biomass, capital and wealth.

;

1-growth phase

2-phase wehre resources are less widely available

3- release or creative destruction phase

4-reorganization and restructuring

Adaption = reaction to drivers and constraints

;

***Panarchy works at different scales and over dif time frames

***Watch video on Buzz Holling, father of resilience theory (http://stockholmresilience.org

Panarchy and Sustainability

*Panarchy makes ‘sustainability not a static condition that need to be preserved for future generations

 

Tradition ‘sustainability’ ignores transcience, transitional states and collapse as normal environmental characteristics

 

Pattern of punctuated change is the norm.

 

PANARCHY/ADAPTIVE CYCLE PROPERTIES

-wealth

-connectedness

-resilience

-transformability

(sustainability can be seen as the collective strength of the above)

Diamond’s Societal Collapse Model

Identifies 5 factors that can contribute to the decline and collapse of civilization:

;

1)environmental damage and population growth

2)climate change

3) hostile neighbors

4)widespread trade partners

5)failure to solve societal problems

;

Must increase resilience to avoid collapse.

How do we promote the adaptive capacity of resource users? (increase resilience of local people?)

www.youtube.com/watch?v=WOQUGtWOsVU

;

Prof Terry Chapin (UAF): plant physiology and Arctic ecosystem ecology, and resilience of social-ecological systems

Tipping Points

Tipping points in a system are the critical threshold of a level of change in a (sub) system after which changes will proceed under their own momentum: like a run-away system.

;

Sometimes the changes after the tipping point are accelerated or step-wise.

;

Many of earth’s potential anthropogenic tipping points are related to the cryosphere

 

Potential Global Warming Triggers:

-Arctic Summer Sa Ice (1-2C)

-Greenland Ice Sheet (1-2C)

-Boreal Forest (2-3C)

-West Antarctic Ice Sheet (3-4C)

-Amazon Rainforest (3-4C)

 

Biodiversity has already hit a tipping point.

Another one has too (read on review)

-Climate change is over halfway there

-ocean acidification and P-cycle are getting there too.

 

AMPLIFICATION

-see Terry Chapin (1:41) video

What are consequences of climate change in the Arctic?

-Rapidity of changes

-Large scale environmental effects

Ice and Biome Distribution/ Peopling of the New World

LGM (~21000BP)

-4.5C colder than today

-ice sheets

-sea level

-permafrost

-loess

-deserts

 

Holocene Climate Optimum (~6000yr BP) “Hypsithermal”

-2C warmer than today

-sea level

-wetter conditions

-lakes

-great lakes formed

-tundra taiga/rain forest

 

How did people come to the new world?

Anthropocene

Present climate state is a “no analogue” state

Term coined by Paul Crutzen to indicate anthropogenic change of natural climate system state -> most clearly defined as starting in 1990s.

 

Ruddimen (2003) argues it started with early agriculture (~8000 years ago)

-deforestation (increased CO2- 8kyrsBP)

-rice cultivation (increased CH4 – 5kyrs)

 

Radiative Forcing…

280ppm pre-industrial CO2

-700ppb pre-industrial CH4

-these values high compared to expected (from solar radiation and natural CO2 trend)

 

Anthopocene saw HUGE population growth

-now 6.9 billion

-impacts include waste, food, industry, agriculture, transport

 

Some main effects of Anthropocene (6)

1) New climate forcings (natural resilience insufficient?)

2)connectivity (globalization

3)monocultures (reducing resiliance)

4)geomorphic agent

5)introduction of foreign substances (pollutants, nuclear material, etc)

6) Cascading effects through positive feedback.

 

Anthropocene, River Basins, and Vegetation

What are the consequences of River and Lake ice, sea ice, permafrost, glacier, and snow decline?

 

River basins have huge hydrological significance, and many waterways are glacier-fed.

 

Present runoff trends in Russian Arctic Rivers variable, but predicted to increase.

 

Present runoff rivers 2x annual P-E over Arctic Ocean

 

-freshening due to estuarine influx changes ocean salinity

-pollution

-sediments

 

Tundra treeline migrating to higher altitudes (1-4m/decade) and latitudes. Mosses colonise ice free rocks in Antarctica.

 

Shrub vegetation expanding in Arctic

-positive feedback due to snow-shrub interactions

Anthropocene Conclusions

Dynamic nature of cryosphere contradicts the classical notion of sustainability

 

View systems over different time periods to understan the processes and ‘cycles’

 

Planners need to include change and uncertainty about the change (as well as possible surprises) into their plans

 

Implement adaptive management techniques

Sheila Watt-Cloutier

~4million people live in the Arctic

~10% indigenous people

 

Canadian Arctic ~50% indigenous

Greenland ~90% indigenous

 

Arctic Council – high-level intergovernmental forum which addresses issues faced by the arctic governments (8 countries) and its indigenous people

 

Inuit Circumpolar Council (ICC) – represents internationally the interests of Inuit in Russia, Alaska, Canada, and Greenland

 

Watt-Cloutia is a Canadian Inuit activist, who made the world aware that climate change is a human rights issue.

-Elected President of ICC – Canada

Spokesperson for Arctic indigenous people in the negotiation of the Stockholm Convention banning the manufacture and use of Persistent Organic Pollutants (POPs)

 

Nominated for the 2007 Nobel Peace Prize (won by IPCC Al Gore)

 

www.youtube.com/watch?v=GISh4XeoLBA

Types of Pollution

Industrial Waste (air/water/solids)

Human Waste

Transport

 

Accidents

Spills

Leaks

Targetted pollution

 

Fires

Volcanic eruptions

Pollution in Himalayas and Antarctica

Himalayas

2006: South Korean mountaineer Han Wang Yong and his international Clean Everest Expedition 2006 team conduct a month long cleaning campaign and collected over 1300kg garbage at basecamp.

 

Antarctica

Alien mammals in Antarctic and subantarctic regions include sheep, rabbits, dogs, cats, rats, mice, and humans

 

Effects on local ecosystems include:

-pollution of station areas by human wastes, and of waters by ships and accidents

-intrusion of flotsam and floating debris in the antarctic waters

-erosion from overgrazing by sheep

-PCBs in lichen

-decimation of bird populations by dogs and cats and of whale and fur-seal stocks by humans

 

Antarctica remains by far the least contaminated land on earth

Under the Antarctic Treaty, it is now a special conservation area.

 

 

At the Antarctic US base McMurdo Station the levels of PentaBDEs (used in flame retardants) were as high as in urbanized areas of North America and decreased with distance from the sewage outfall.

Pathways of Pollution

Air

Precipitation

Oceans

Rivers

Soil

Ice (sea and glaciers)

 

Local vs Global

-often long-range transport

 

Visitor invasion

Industrial activity

 

**Chaning pathways due to climate change***

-open water

-air flow patterns

-melting permafrost

 

 

Important Pollutants/Toxic Chemicals

POPs (persistant organic pollutants)

legacy POPs: industrial byproducts (PCBs, PCDDs (dioxins), and organochlorine pesticides (DDT, chlordane, diendrin, toxaphene))

Emergent POPs = brominated flame retardants (BFRs), endosulfan and lindane, fluorinated compounds (in non-stick coatings and stain repellents)

 

ORGANOPHOSPHATE PESTICIDES

-insecticides, herbicides, nerve gas, solvents, plsticizers, and extreme pressure additives (for lubricants)

-degrade rapidly by hydrolysis on exposure to light, air, soil

-small amounts can be detected in food and drinking water

 

MERCURY

-slowly phased out in scientific equipment

-asia currently 50% of emissions

 

Pb/Zn/Cu

-pipes, fillings, paint

 

RADIOACTIVITY

-many contaiminants accumulate in fatty tissue

 

__________

 

Some good news!

US clean air act (1972 and 1996) and world-wide ban phasing out of leaded gasoline/petroleum.

-decrease in nitrate, and later in Pb concentrations

 

LOTS OF BAD

-game sea birds, particularly eider, contain high concentrations of lead (but this is because the use of ‘lead shot’ in hunting the birds

-human blood lead concentration is higher with the more sea birds consumed.

Radioactive Polluton

Radioactive ice cores found and can accurately date nuclear testing, chernobyl, and the testing ban.

 

Russian underground nuclear explosions (71-88) occurred in the norht quite often.

 

There were 43 underground explosions in Novaya Zemlyabefore 1991.

 

There is a great amount of radioactive material in the world. The potential exists for climate change to mobilize it.

 

EFFECTS
-acute radiation Syndrome (death due to high doses)

-birth defects

-cancer

-damaged DNA (less resilience)

-reproductive system

-etc. etc. etc.

 

input-atmosphere-earth’s surface=diet=tissue=dose

-can skip steps

;

;

PROJECT CHARIOT (58-62)

US Atmoic Energy Commission proposal to detonate a string of underground nuclear devices at Cape Thompson on the N Slope of Alska

;

Inupiat vilage of Point Hope -; hunting grounds in the area…

;

Prediction of Pollution Effects

Heat and salt content are important factors affecting

1)the functioning of polar ecosystems

2)the rates of substance flows

3)the stratification of the water, internal waves, circulation patterns, sea ice distribution

;

In order to predict and make timely decisions after teh appearance of undesirable trends or extreme environmental situations, it is necessary to understand enviornmental processes, and construct models of abiotic and biotic relationships.

Ecosystem Pollution and Arctic Foodwebs

Ecosystems have 4 basic components:

1)the abiotic environment

2) producers (autotrophs)

3) consumers (heterotrophs)

4) decomposers

;

Energy cycles through them

;

trophic level the position that an organism occupies in a food chain

-what an organism eats and what eats the organism

;

*Marine food webs have more tropihc levels than terrestrial food webs

;

The Tundra Biome

-Productivty very low

-Recovery from any distrubance is very slow as tundra is a very delicate and fragile biome

;

Timescale of ecological processes in relation to natural disturbances in the Arctic…. NO FAST RESPONSES

;

How do Contaminants get concentrated in Cold Environments?

Solvent Switching

-ie. all of the contaminant moves from air to water: increased concentration in water

;

Solvent depletion

-removal of solvent by a variety of processes

-can lead to “fugacity amplification” (fugacity reflects the tendency of a substance to prefer one phase (liquid, solid, or gas)

-Read about this, and look at diagram (lec9p5)

;

Bioaccumulation

-organism absorbs toxic substance at a greater rate than that at which the substance is lost

-within a trophic level

;

Biomagnification

-increase in concentration of a toxic substance in a food chain resulting from a)persistence (slow degradation), b)food chain energetics, or c) low rate of internal degradation/excretion (often due to water-inslubility)

-ie DDT

;

Combined effects

Arctic pollution and glacier melt

DDT levels in the Adelie penguin have been unchanged since the 1970s, despite an 80% reduction in global DDT use (has been banned in N hemisphere)

;

1-4kg of DDT are released into coastal waters annually along the W Antarctic Ice sheet from glacial meltwater

;

Glacier melt a probable source for DDT pollution of Antarctic marine systems

____

;

MELTING ALPINE GLACIERS: POPs Released

www.youtube.com/watch?v=vxqf4GmHDNA

-post-1990s peak

-relevant release of POPs from melting Alpine glaciers

-input fluxes from the high-alpine lake Oberaar into the lake sediment

______

;

EFFECTS of both biomagnification and solvent depletion in glacial stream in the Italian Alps

-peak in July possibly from solvent depletion (rain and melting of snow)

-Glaciers and snow are temporary sinks for atmospherically transported pollutants

Bioaccumulation ; Biomagnification

;

Causal link b/w POPs and adverse health in top predators

-hormone, immune and reproductive systems

;

Many indigenous populations in the Arctic have poorer health than the national averages = combination of western food, lifestyle choices and polluted food.

-cardiovascular, reproductive, hormone, neurological, metabolic and immune systems

Traditional food remains important for social, cultural, nutritional, economic and spiritual reasons.

Air Pollution

SMOKE FROM FIRES

;

ARCTIC HAZE

-reddish-brown smog (mostly N of 60N)

-Sulfuric acid, nitrogen and organic aerosols formed in the air from the combination of naturally occurring chemicals and pollutant sulfur dioxide or hydrocarbon gases.

;

Aerosols smal enough to float in the air, but large enough to reflect sunlight, and cause haze.

;

Arctic haze also carries a mes of airborne toxic contaminants, heavy metals, and industrial organic compounts

;

It is seasonal. Peaks in late winter and spring and is most severe when stable, high pressure systems produce clear, calm weather. Removed by wind or rain. This rain is often acid rain.

;

WHY does it form over the arctic region???

;

Arctic haze is the result of the ‘trapping’ of air masses in Arctic Dome (or cold air) that sits over the N Pole region. The Arctic Dome is confined by the Arctic front, which is the boundary between polar and arctic air masses and lies to the north of the Polar Front (boundary of polar and warmer air masses).

;

The Arctic Front is discontinuous and wavy and depends on the temperature contrast between two air masses. It is particularly prominent during summer in N Eurasia.

;

Arctic haze can appear in distinct ‘bands’ or ‘layers’ at different heights because warm dirty air is forced upward. These bands can be 10-1000m thick and can extend over 20-200km. Within the bands, visibility can sometimes be just a few km.

;

Source Regions

-smelter complexes in Siberia (largest source of sulfur dioxide emissions within Arctic region is at Norilsk)

;

NAmerica contributes most ozone, Europe contributes most sulfate, black carbon. CO is mostly equal for all sources.

;

SOURCE REGION SENSITIVITY

Sensitivities show strong seasonality…

1) surface sensitivities typically maximize during boreal winter for European and during spring for E Asian and N American emissions

2)Mid-tropospheric sensitivities nearly always maximize during spring or summer for all regions

3)Deposition of black carbon (BC) onto Grenland is most sensitive to N American emissions.

Exxon Valdez

Exxon Valdez (1989)

ww.youtube.com/watch?v=MbjC9SMKClE

;

Exxon Valdez ran aground on a well-known reef and spilled 11million gallons of crude oil

-one of the largest spills in US history and one of the largest ecological disasters

-one of very few oil disasters in Arctic regions

;

Timeline for recovery depends on substrate:

-bedrock shorelines in wave zone :weeks

-exposed sandy beaches: months

-marshes and salt flats: years to decades

;

Oil in sediments (sand/silt/clay) will remain there fore years/decades.

;

Prince William Sound has made a remarkable recovery from a severe injury, but it remains an ecosystem in transition, 20yrs later:

-26000 gallons Valdez oil still in Alaska’s sand/soil

-Deeply penetrated oil still leaches from a few beaches

-in some areas, intertidal animals (mussels) are still contaminated by oil

-some rocky sites that were stripped of heavy plant cover by high-pressure, hot-water cleaning remain mostly bare rock.

-Rich clam beds that suffered high mortalities from oil and extensive beach cleaning have not repopulated to previous levels

Pollution in Chernobyl, Rockies, and Tibet

RECENT CLIMATE EXTREMES ALTER ALPINE LAKE ECOSYSTEMS

-Alpine lake ecosystems responsive to interannual variation in climate, based on long-term limnological and meteorological data from the Canadian Rockies

 

In 2000s, rel to 1990s, in years with colder winters, higher snowfall, later snowmelt, shorter ice-free seasons, and drier summers, alpine lakes:

1)became clearer, warmer, and mixed to deeper depths

2)became more dilute and nutrient poor (leading to declines in total phytoplankton biomass)

3)had increased concentrations of dissolved organic carbon (stimulating the appearance of small mixotrophic algal species, partially offsetting the decline in autotrophic phytoplankton biomass)

 

CHERNOBYL

-1 of 15 worst places to live

-1986, home to over 14k residents, now is uninhabited due to contamination

-worldwide spinach, mushrooms, lichen, caribou

 

LA OROYA

-one of 15 as well

-in Peru

-a soot-covered mining town in the Peruvian Andes

-99% of the children who live here have blood levels over acceptable limits for lead poisoning, which can be directly attributed to an American-owned smelter that has been polluting the city since 1922.

www.youtube.com/watch?v=Dc205KfQ7aA

www.youtube.com/watch?v=VguzDVY7NAM&feature=related

 

MINING TIBET

Mining operations in Tibet have been booming since the arrival of the Qinghai-Tibet rail line in 2006, bringing wealth to local governments and mine owners.

 

Little benefit to local Tibetan farmers and nomads who say the mines scar mountains they consider sacred and kill the yaks and sheep they need in order to make a living

 

Protests against China’s billion-dollar mining industry are rising.

Precautionary Principle, Future threats, and Arctic Charter

In order to protect the environment, the precautionary approach shall be widely applied by States according to their capabilities. Where there are threats of serious or irreversible damage, lack of full scientific certainty shall not be used as a reason for postponing cost-effective measures to prevent environmental degradation.

;

Future Threats…

-NW and NE passages

-pop increase

-climate change

-new pollutants

;

ARCTIC CHARTER?

www.youtube.com/watch?v=D4CXCGWEbgQ;feature=related

;

Conclusions of the ALDE Conference on Arctic Governance (2008)

-Borders and jurisdiction are not seen as the main obstacles for Arctic governance

-environmenta changes and risks from human activity are the most important challenges

-inerconnectedness of the arctic ecysystems should have implications for its governance

-the regime in the Antarctic cannot be transferred to the Arctic; the two polar regions are totally different from each other in so many perspectives

-existing treaties must be ratified, implemented and strengthened

-at the moment it is not politically and legally feasible for a broad, binding legal regime at a regional Arctic scale (yet there is need for strategic coordination)

-there are limitations in teh functionality of the Arctic council (scientific agenda), limiting the possibilities of acting as a strategic coordinating body

-International collaboration, including nations outside the arctic, where most pollution is originating from, through partnership and stewardship.

How Animals Survive in Cold Regions

David Attenborough: The Frozen Seas

Narwhals: www.youtube.com/watch?v=44sjE_x1X4k

;

PHYSIOLOGY

Reduce area:volume ratio

Fat or Blubber

-distribution

-amount

-type

Fur/Feathers – not such good insulators in water unless coated, not great in wind

Cardiovascular System

-antifreeze in blood (frogs)

-vascular counter-current heat exchanger (fish)

;

;

BEHAVIOUR

Hudddling

-penguins, bees

Heliothermic Behaviour

-butterflies

-lizards

Muscle Contractions

-snakes

Hibernation

-mammals

Migration

-birds, butterflies, caribou, lemmings, narwhals and whales

Movement to keep ice open (warmer and can breathe)

-ducks, whales, seals

;

Fattening up for winter!

Rain on Snow Events

In October 2003, a severe ROS event killed ~20 000 musk-oxen on Banks Island, westermost island in the Canadian Arctic

;

The event reduced the isolated herd by 25% and significantly affected the people dependent on the herd’s well-being

 

ROS induced water and ice layers facilitate a) the growth of toxic fungi 2) significantly warm the soil surface under thick snowpack and 3) the hard snow crust deters large grazing mamals (musk oxen and caribou)

 

 

ROS events are defined as a minimum of 3mm of rain falling on a minimum of 5mm of snow w.e. (~5cm snow)

 

Increased frequency of ROS events in much of northwestern NA: habitat for several types of caribou.

How Plants Survive in Cold Climates

David Attenborough…

video.google.com/videoplay?docid=303372183419001614#

 

 

Migration

-light, wind-dispersable seeds

-dispersal by water

-Use animals as vehicle to carry the seeds (berried cruits attractive to birds, burrs sticking onto fur, seedpod that are grazed)

-seedlings dispersed when snowpack is covering land (smooth terrain, more wind, less chance of getting stuxk at close distance)

 

PHYLOGENY

For diverse species (but not all) climate and extreme weather events are mechanistically linked to:

-body size

-individual fitness

-population dynamics

 

Phenoly

Study of periodic biological events as influenced by the environment

Bio0indicator for global change and a determinant in climate change impact studies

 

Last 100-150 years:

-butterfly species showed diagnostic patterns of N expansion (new colonizations) and S contraction (population extinctions)

 

Sign switching should occur as a response to opposing short term trends in climate (Warming vs cooling):

-typical pattern: N range shifts during teh two 20th century warming periods (1930-45 and 1975-99) and S shifts during the interveneing cooling period (50-70).

Alpine Tree Lines

Both N-S and E-W gradient

-will be lower on N slopes

 

Alpine tree lines are climatically-determined ecotones (particularly sensitive to T change)

ecotone is a transition area between two adjacent but different plant communities

European Alps 20th Century: +2C and 1C since 1980

-Average Alpine T lapse rate = 0.55C/100m (potential tree line shift of 200m)

 

Get different tree communities and different tree lines depending on climate (ie, for alps Mediterranean, Continental, or Maritime)

 

Treeline species (Switzerland) show:

1)increased growth rates

2)changing plant communities

3)increased young tree establishment

BUT..

two anthro disturbances…

1)rapid climate change

2) land use change *abandoned agricultural land at higher elevations

 

Average upward shift in 12 years: 38m

-1/4 started without pre-established woody vegetation (shrub)

 

Treelines elsewhere….

NW CAN/GNP/Urals

-minor changes in upper limit last 150 yrs

-increase in density

 

FRENCH MOUTAINS

-more than 2/3 of 171 forest species moved over 18.5m per decade during 20th century

 

Sedish Scandes

-max 200m and means of 70-90m in last 100yrs

-rapid upward advance since 1950s

-spread of broadleaved thermophilic tree species into subalpine forest belt

Consevative Behaviour of treeline changes

Be careful in interpretation of tree line shifts over periods <50years!!!!

-No complete forest establishment: hard to find exact treeline in first place

-Permafrost and soil patchy: delayed establishment

-Frequent stochastic processes (avalances, snow creep)

-lagged response due to seed dispersal and tree recruitment peak processes (regeneration pulses >10-20yr period)

-subalpine meadows resistant to tree invasion

-in man yalpine regions during Holocene upper treeline in alpine shifted <100m N and S shifting is more sensitive than up and down?

 

Trees are long life species and have low dispersal rate!

-ability to adapt genetically or to seek refuge is limited if climate change is too abrupt

-at present, their phenology has been less modified by T increase than other functional groups

 

However, climate change can supersede the adaptive capacity of trees, esp if they can not seek refuge (migration is often the only way)

Parmesan and Yohe (Nature, 2003)

META-ANALYSIS Study of Phenology, Range and Distribution

-quantitative meta-analyses of 334 species

-qualitative global analyses of 1570 species (functional/biogeographic groups)

 

Highly significant, nonrandom patterns of change in accord with observed climate warming in the 20th century, indicating a very high confidence (95%) in a global climate change fingerprint.

 

Climate is an important driving force of natural systems and even though the driving force might be relatively small, the impact is consistent:

1)systematicaly affects century-scale biological trajectories

2) ultimately affects the persistence of species

 

A) PHENOLOGICAL (TIMING) SHIFTS

-quantitative analysis of plants/animals: mean shift towards earlier spring of 2.3 days per decade

-qualitative analysis of 677spp 62% showed trends towards spring advancement

 

B)RANGE BOUNDARY SHIFTS

99 spp of birds, butterflies and alpine herbs

-Range limits of spp have moved on average 6.1 km/decade N

-significantly in direction predicted by climate change

 

C)COMMUNITY SPP DIST/ABUNDANCE

Qual. anal. ~900spp

-neither support nor refute a climate change signal

-will be important for predictive biological models to eventualy determine what proportion of these are truly stable systems

 

Range Distribution Shifts

-New spp have colonized previously ‘cool’ regions

-Some arctic spp have contracted in range size

-over past 40 yrs, max range shifts vary from 200km (butterflies) to 1000km (marine copepods)

 

REGIONAL SUMMARY

-Difference b/w polar and temperate spp

Polar: stable or decline

Temperate: increased in abundance and/or epanded distributions.

www.youtube.com/watch?v=R34zshFRgbw

A changing landscape: investigating a warming climate

 

Also find and watch movie on Svalbard Global Seed Vault

Periglacial environment

Periglacial processes characerise regions with cold climates

-periglacial used to describe proceses and features in areas adjacent to modern ice sheets

 

A periglacial environment is difficult to define..

-precise temp/precip

Ventifacts

WHAT?

-stones shaped and polished by wind abrasion

-aeolian transported sand is dominant factor

Created by sand moving in the saltation zone

 

FACETS

Can be 3- or 4-siders

-3=dreikanter

4=vierkanter

 

Produced on surfaces nearly perpendicular to wind direction

 

PITS

-small depressions eroded into surface

-best developed on steep surfaces facing prevailing wind

-begin and grow from points of weakness

-what are some possible points of weakness?

 

GROOVES

-U-shaped depressions

-grow from pits

FLUTES

-extend across the rock surface linearly on surface facing wind

-aligned parallel to strongest wind direction

-most reliable type for determining wind direction

 

YARDANG

-Larger scale ventifact

Wind eroded ridge that is elongated parallel to prevailing wind (typically 2-3 times longer than they are wide)

-usually less than 10m high

Can extend for kilometres

Stoss side is blunt and steep

Common in regions underlain by relatively soft rocks

 

HOW are ventifacts important?

-provide useful information about periglacial wind conditions both past and present

-former wind conditions are useful for reconstructing periglacial environments

Desert Pavement

Surface is only one or two stone layers thick

Fine sediment under stones

 

Removal of finer sediments from the surface

This causes deflation

Once finer sediment is removed and only rocks are exposed, wind threshold cannot continue to erode

 

WHERE?

Common in aluvial fans and unsorted deposits

Occurs under very windy conditions

 

How is it periglacial?

-alluvial fans from glacial outwash

-katabatic winds next to a glacier

 

Importance?

-rocks in the pavement can be ventifacts

-ventifacts help determine wind regime of past

-wind regime can help reconstruct past climates

LOESS

Wind deposited sediment

Loess deposits blanket the landscape

 

over 50% silt, 5-30% clay, and 5-10% fine sand

 

STRUCTURE

-particles angular

-porosity less than 50%

-highly cohesive

-sudden collapsibility when saturated

-forms nearly vertical exposures

 

SouRCE?

-cold climate periglacial sediment deposits

-originates from flood plains, (ie outwash from glacial streams)

-silt and clay is transported by the wind as dust, it is called loess when it is deposited

-thus, loess does not necessarily indicate a periglacial enviornment due to aeolian trasportation

 

Thick loess sheets of central Europe, Russia, and China were deposited in glacial periods.

Warmer climatic conditions allow organic layers (Paleosols) to form on the loess deposits

-paleosols can be carbon dated

-can reconstruct past climatic conditions

-Thus, loess deposits are archives of past climatic conditions and environmental changes

Sand Dunes

Assymetrical mounds of sand that migrate by aeolian erosion

Contains: backslope, crest, slipface

 

What are requirements for periglacial sand dunes?

-sediment supply

-wind

-lack of veg

-climate (arid, semi-arid)

 

How are they periglacial?

Sediment supply originates from glacio-fluvial and glacio-lacustrine sediment from glacial outwash and melt water

-katabatic winds drive the formation of the dunes

 

Barchan dunes vs Parabolic dunes

-unidirectional wind

 

Transverse dunes

-unidirectional wind

-ridges of sand with steep stoss face

-barchan dunes transform into transverse dunes if the sediment supply increases

 

Linear Dunes

-form parallel to prevailing wind irections

-wider and steeper at upwind end

-tapering downwind

-form in areas with limited sand supply

Commonalites (ventifacts, loess, desert pavement, and sand dunes)

All rely on :

-sediment supply

-aeolian activity

-vegetation

-climate

 

Each landform occurs in a transitioning landscape relative to periglacial environments

-ventifacts occur in areas with unsorted deposits and katabatic winds from glacier

 

loess originates from outwash of glacial streams. Deposits indicate glacial and interglacial periods.

 

Desert pavement is common in alluvial fans and unsorted deposits. Kat winds from the adj glacier.

 

Dunes are supplied by glacial outwash sediment … again katabatic winds.

Measuring the Cryosphere

The cryosphere is the most sensitive to changes in climate of all environmental systems at the earth surface…

 

BUT

 

..relatively few measurements because of geographical remoteness, large scale, extreme conditions, extreme variability, and the long time-scale of some cryospheric processes.

Review- Cryosphere components and trends

Sea ice, ince 1978, has decreased in extent by about 2.1% per decade (slope of -9)

 

 

Northern lakes are experiences earlier freeze and later breakup dates.

 

Mean lengths in global glacier tongues are all decreasing (small variability).

 

RESPONSE TIMES

Very slow!!

Snow, river/lake/sea ice: day to month

Glaciers/Ice caps: months to centuries

Frozen ground: days to millennia

Ice sheet margins: months

ice shelves: years

ice sheets: millennia

Relevance of Tayler’s presentation
Landscapes in transition!
Regions where glacier hazards are currently problematic

BC: moraine dammed lake outbursts following recesion

;

N Andes/Cascades: outburst floods from glacier topped volcanoes

;

Peruvian Andes: Moraine dammed lake outbursts following glacier recession

-ice avalanches

-debris flows

;

Iceland: outburst floods from subglacier volcanic eruptions

;

European Alps: ice avalanches

-GLOFs from recession

-debris flows

;

Caucasus mtns: Rock/ice avalanches

-debris fows

Tien Shan Mountains: Glacier dammed lake outburst following glacier advances

;

Karakoram/Himalaya:

-GLOFs (recession)

-GLOFs (surges)

Paraglacial sediments

Large fluctuations in energy/size of sediment

;

Angular, large boulders

;

Gully incisions

;

PARAGLACIAL SEDIMENT REWORKING

-The paraglacial period of enhanced sediment yield commences at deglaciation and terminates when sediment yield is indistinguishable from the ‘gological norm’ resulting from primary denudation of the land surface by subaerial processes.

;

**review this graph (in review)

;

At commencement of deglaciation, sediment yield increases a little bit then gradually goes down and levels off

;

That which is attributed to glaciation is the entrainment of paraglacial rock-slope debris.

;

Geological norm consists of debris input from valley walls and subglacial abrasion and quarrying

;

Also study paraglacial exhaustion curves (next slide)

;

Some tipping points…

Boreal Forest DIe Back..

;

Melt of Greenland Ice Sheet

;

Arctic Sea Ice Loss

;

Instability of West Antarctic Ice Sheet

;

Atlantic Deep water Formation

;

Changes in ENSO Amplitude/Frequency

;

West African Monsoon Shift

;

Indian Monsoon chaotic multistability

;

Permafrost/Tundra loss

;

Climate change induced ozone hole

;

Sahara greening

;

Tipping points of chemical polution and atmospheric aerosol loading have not yet been quantified…

;

Already past tipping points for biodiversity loss and Nitrogen cycle (biogeochemical flow boundary)

Do all the tasks!!!

Data exploration task (google earth) prob testable..

;

Taught us to:

1)understand presented phenomena

2)think about the wider implications

3)think critically

Hocky stick graph

Temperature change!

Comparison of NH temperature proxies with model simulations over the past 1000 years, and T record extension to 2000 years using long proxy temp data series

;

;

Climate denial with Peter Sinclain (crock of the week)
www.youtube.com/user/greenman3610#
Review… energy balance

KNOW :

-net radiation

sensible heat flux

latent heat flux

subsurface heat flux

;

Some main, broad effects of the anthropocene

1) connectivity (globalization)

;

2)cascading effects through positive feedback

;

3)new climate forcings (natural resilience insufficient?)

;

Nuclear testers
Mostly USA, lots of USSR/Russion, some France, UK, China, India, Pakistan, DPRK
Review: Solvent Depletion Process… WTF?

Meta-Analysis (Parmesan and Yohe) summary

;

Highly significant, nonrandom patterns of change in accord with observed climate warming in the 20th century, indicating a very high confidence (95%) in a global climate change fingerprint.

;

A. Phenological shifts

B. Range boundaries shift

C. community and/or species distribution and abundance

;

Climate is an important driving force of natural systems and even though the driving force might be relatively small, the impact is consistent:

1)systematically affects century-scale biological trajectories

2)ultimately affects the persistence of species

Review: Environmental Change and Culture

Environmental Change in Northern Ungava

-mining, tourism, trade, industrial activity

-climate change

-sea level change

-ecological changes

-pollution, alcohol

-politics (now part of Quebec)

;

Effects

-materials

-traditional knowledge

-ecology

-landscape

-population health

-people’s self-esteem and dignity

 

Socio-economic, cultural and psychological effects

 

Review…. Annual calendars of cold region cultures..

-when to bring sheep into mountains, and when to bring them down again

-stages of fires, etc.

-Shepherd life at Nuria, Spanish Pyrenees

-see pg 28 of textbook

 

-mixed cultures in these regions

 

KANANGINAK POOTOOGOOK 1935-2010

Cape Dorset print maker and artist.

The “Audubon’ of the North

-arctic evening

-alcohol

-watching the simpsons

-stranded on the ice floes

;

**review “Sources of Social and Economic Resilience and Vulnerability that Characterize Arctic Systems”

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