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Global Change: A Paleoclimate Perspective from the World’s Highest Mountains

2008 Jim Arnold Lecture UC San Diego, May 9, 2008 Lonnie G. Thompson University Distinguished Professor School of Earth Sciences & Byrd Polar Research Center The Ohio State University

Ice Core Paleoclimate Research Group Ellen Mosley-Thompson Funding provided by: Henry Brecher NSF: & Polar Mary Davis Programs Paolo Gabrielli NASA: Earth Sciences Ping-Nan Lin NOAA: Paleoclimatology Matthew Makou Comer Foundation Victor Zagorodnov Graduate Students: Liz Birkos, Aron Buffen, Natalie Kehrwald, David Urmann, Lijia Wei Objectives:

• Introduction to

, among the first responders to global warming, serve as both indicators and drivers of climate change

• Evidence for , and present

• Evidence for recent acceleration of the rate of ice loss in the tropics – A Clear and Present Danger!

• Options: prevention, adaptation and suffering

• Conclusions Our Earth is warming! Environmental conditions are changing! - some changes are unprecedented for thousands of years - some changes are occurring rapidly (years to decades) (shrinking sea ice, ecosystem disruptions, retreating and melting glaciers)

2005 warmest year on record

0.7°C

relative to the 1961-1990 mean

http:www.giss.nasa.gov/research/news Natural mechanisms influence climate

Natural mechanisms

• Changes in the Sun

• Changes in the amount of volcanic dust in the

• Internal variability of the coupled atmosphere-ocean system (e.g., ENSO, monsoon systems, NAO) factors also influence climate

Non-natural mechanisms

• Changes in the concentrations of atmospheric greenhouse gases

• Changes in and particles from burning fuels (sulfate aerosols) and ()

• Changes in the reflectivity () of the Earth’s surface

Smoke from fires in Guatemala and Mexico (May 14, 1998) Earth’s ice sheets and glaciers preserve long, high resolution histories

High temporal resolution

East Plateau

Long records

20021977 Quelccaya , Peru Ice cores are powerful contributors to multi- reconstructions: 1) they provide multiple lines of climatic & environmental evidence 2) ideal for revealing rapid climate changes

(δ18O, δD)

Guliya ice cap, Tibet Class-100 clean room houses the equipment to analyze dust, and chemicals

Freezers for storage and cold rooms for physical property measurements

Machine shop for fabrication of our drills Vostok

The Vostok extends back through multiple glacial and interglacial stages - recording the changes in the composition of the Earth's atmosphere Today: Today: 385 CO2 is 385 ppmv CO2 is 378 ppmv CH4 is 1750 ppbv CH4 is 1750 ppbv

Houghton et al., 2001 Petit et al., 1999 and concentrations: Past, present and future By 2100:

CO2 remains in the 850 CO2 ~ 850 ppmv atmosphere from 70 to 120 years IPCC 2000 Scenario A1B for 2100 AD By 2100:

CH4 ~ 3700 ppbv

Today: CO is 385 ppmv 385 2 CH4 is 1750 ppbv

Houghton et al., 2001 Petit et al., 1999 Proxy Records Provide A Critical Time Perspective

5 IPCC 4th Assessment (2007) Projection for 2100 AD 4 2.0 – 4.5 oC 3

2 Global (°C)

Northern Hemisphere N.H.Temperature Temperature (°C) (°C) 1

0.4 0 0 -0.4 -0.8 1000 1200 1400 1600 1800 2000 YearYear (A.D.) A.D.. 11 Ice cores provide unique histories …… from regions where other recording systems are limited or absent

Huascarán, Peru

Dasuopu Southern Tibet Sites where the OSU team has drilled ice cores DUNDE ICE CAP, CHINA CORE SITES, 1987 SUMMIT CORES

D UNDE IC E CAP, C HINA

SUMMIT CORECORES SITE, 1987 EQUILIBRIUM LINE EQUILIBRIUM LINE

South America BPRC1

Ice core drilling on the Coropuna Ice Cap, Peru (2003) Coropuna, Peru Chironomidae 1260± 380 yr. B.P. length: 0.7 mm

Sajama, Bolivia Heteroptera 5620 ± 275 yr. B.P. length: 2.0 mm

Side of Quelccaya ice cap, Peru

Annual layers

-12

-14

-16

-18 per mil per

-20

-22 Quelccaya 2003 Summit Dome -24 Average of Quelccaya 1983 cores

1550 1575 1600 1625 1650 1675 1700 1725 1750 1775 1800 1825 1850 1875 1900 1925 1950 1975 2000 Year

-12

-14

-16

-18

-20 O annual averages

18 -22 δ

-24 R2= 0.82 2003 -26 -26 -24 -22 -20 -18 -16 -14 -12 -10 1983 δ18O annual averages

Tropical Composite (Temperature)

Tropical Composite () 77 new High elevation, low latitudecores ice cores record - large-scale climate changes - regional differences

No LIA

No MWP

LIA

MWP

Thompson et al., PNAS, 2006 77 new High elevation, low latitudecores ice cores record - large-scale climate changes - regional differences

No LIA

No MWP

LIA

MWP

Thompson et al., PNAS, 2006 77 new High elevation, low latitudecores ice cores record - large-scale climate changes - regional differences

Reference period (1961 – 1990 A.D.)

LIA

MWP

ThomThompsonpson et al.et ,al. PNAS, PNAS,, 2006 2006 McCall Glacier, Brooks Range, Alaska

Austin Post,1958 Matt Nolan, 2003 Muir Glacier, SE Alaska

August, 1941 (photo by William Field) August, 2004 (photo by Bruce Molnia) AX010, Nepal 1989 , 1978

1998 2004

Photos: Koji Fujita Massive retreat of low-latitude glaciers today

2002

Gangapurna Glacier

Courtesy Doug Burbank, UCSB Massive retreat of low-latitude glaciers today

2002

Gangapurna Glacier 1957

Courtesy Doug Burbank, UCSB ~ 2 - 3 m thinning / year Ghiacciai della Lobbia e dell’Adamello/Mandrone (102 anni)

Foto: Archivio Storico – Biblioteca della Montagna SAT 1903 Foto: G. Alberti CGT 2005 Ghiacciaio de la Mare (7171 annianni)

2003 (Foto L. Carturan CGT)

Zonal Distribution of Annual Precipitation

Image from GOES-12 Satellite Nov 4, 2004 DJF Uniform tropical upper-air temperature

DJF Larger SST variations

DJF Rainfall roughly follows warm SST

(Sobel and Bretherton, J. Climate , 2000 mos. relative to peak El Nino

1000-300 mb average air temperature anomalies associated with ENSO (MSU2) gray: 0.2-0.4 (peak Nino3.4) black: >0.4 K

Warming spreads nearly uniformly around the tropics

(Chiang and Sobel 2002, J. Climate) Aerial photo in 2000

Drill shelter on Northern Ice Field, Kilimanjaro in 2000 Kilimanjaro (2000) Northern Ice Field Core 3

Tube 1: top: 0.00 m Elongated bubbles

Tube 43: top: 42.84 m Outburst of and ice collapse on Fürtwangler Glacier (Kilimanjaro) in spring of 2003 16 Feb 2000 28 Jan 2006

15 Oct 2007 Furtwängler Glacier

16 Feb 2000

28 Jan 2006

15 Oct 2007

Himalayan glaciers store about 12,000 cubic kilometers of freshwater in ~15,000 glaciers and are the lifeline for millions of people (IPCC, 2007)

Retreat of the Qori Kalis Glacier (Peru)

1978 – no lake

2004 – lake covers 78 acres Qori Kalis, July 2005 Qori Kalis, July 2006

2006 – lake covers 84 acres

1977 2006 Boulder, 1978 Boulder, 2006

Glaciers, especially tropical glaciers, are “the canaries in the mine” for our global as they integrate and respond to most key climatological variables such as temperature, precipitation, cloudiness, humidity and radiation.

• Global glacier retreat at the beginning of the 21st Century is driven mainly by increasing although regional factors (i.e., deforestation also may play a role). Martin Chambi J. Mid-1930’s Qoyllur Rit’i, Peru 2006

In 1915 Ernest Shackleton stated …… “What the Ice Gets, the Ice Keeps”

But today the retreating ice is giving up long-buried secrets ….. Quelccaya, Peru

1977

2002 Quelccaya Ice Cap, 2002

200 – 400 m above its Plant modern range

5177 ± 45 yr. B.P.

The Kilimanjaro ice cores provide a record ~ 11,000 years long

This abrupt cooling event 5,200 years ago was contemporaneous with the reorganization of societal structures – Late Uruk abrupt climate change - Hierarchical societies formed in the overpopulated Nile Valley & Mesopotamia; - Neolithic settlements in the inner deserts of Arabia were abandoned Global, synchronous climatic change ~ 5 – 5.6 kyr B.P.

Magny and Haas, 2004. J. Quat. Sci. • “One of the warning signs that a dangerous warming trend is under way in Antarctica will be the breakup of ice shelves on both coasts of the , starting with the northernmost and extending gradually southward.”

• Concluding statement in Mercer, 1978 Vol. 271 Temperatures in the Peninsula region have warmed ~2.0oC in the last 50 years. Part of the Larsen B Ice Shelf Jan 31 collapsed in 31 days (2002)

Feb 23

Mar 3 Collapsing ice shelves don’t 10% Floating ice shelves do not directly raise . contribute to . 90% But, the loss of their buttressing effect, land-based glaciers flow faster and discharge more ice into the ocean raising sea level.

Since 2002 some glaciers are now flowing 7 to 8 times faster. Some have thinned up to 40 meters in 6 months.

Glaciers that feed the remaining parts of the ice shelves have not accelerated.

Scambos et al., 2004 observations The warming in the Arctic is now well-documented ….. Arctic Climate Impact Assessment available at http://www.acia.uaf.edu/

East : summer melt water running into a moulin

Photo by Roger J. Braithwaite Greenland – losing mass overall

Gaining mass (increased precipitation) at high elevations

Losing mass rapidly along coast

Overall balance: -100 Gigaton (Gt) annually

360 Gt of water = 1 mm of eustatic sea level rise

82 Gt is ~1.5 months of Shepherd & Wingham, Science, 2007 U.S. water consumption West Antarctica & Peninsula – losing mass: - 50 to - 200 Gt annually

East Antarctica – gaining mass: +25 to - 4 Gt per year

Antarctica is losing mass: - 25 to -204 Gt annually

360 Gt of water = 1 mm of eustatic sea level rise

82 Gt = 1.5 months of U.S. water consumption Shepherd & Wingham, Science, 2007 Rignot et al., Nature Geoscience, 2008

In the last decade – many glaciers draining the two large ice sheets have accelerated their discharge to the ocean by 20 to 100% (highly variable).

How will they behave in the future? •Climatologically we are in unfamiliar territory, and the world’s ice cover is responding dramatically. Sea level is currently rising 3.1 ± 0.7 mm per year. This is due to - thermal expansion of ocean (~50%) Ice Sheets are the - alpine glacier mass loss (~30%) Potential Wild Card!! - mass loss (~10-20%) - pumping groundwater (irrigation) – few % Antarctica Greenland 6 to 7 meter sea level rise equivalent

East Antarctica 55 to 60 meter sea level rise West Antarctica equivalent 5 to 6 meter Currently, 60% of the ice loss is from glaciers and ice sea level rise caps rather than the two ice sheets. The loss from equivalent mountain glaciers may raise sea level ~ 0.25 meters by 2100. (Meier et al., Science, 2007) Courtesy of Dan Schrag, Harvard Univ. Courtesy of Dan Schrag, Harvard Univ.

So society has three options!

• Prevention, means taking measures to reduce the pace & magnitude of the changes in global climate being caused by human activities. Examples of prevention include reducing emissions of GHG, enhancing “sinks” for these gases, and “geoengineering” to counteract the warming effects of GHG.

• Adaptation, means taking measures to reduce the adverse impacts on human well-being that result from the climate changes that do occur. Examples of adaptation include changing agricultural practices, strengthening defenses against climate-related disease, and building more dams and dikes. But it’s a moving target!

• Suffering, the adverse impacts that are not avoided by either mitigation or adaptation.

Key points made in this presentation

The 20th century is the warmest in the last 2000 years as recorded in low latitude ice cores and in several places is the warmest in over 5000 years. Ice cores provide unique information that extends our knowledge of Earth’s climate history. Climatologically we are in unfamiliar territory, and the world’s ice cover is responding dramatically. Observed rapid changes in Greenland and Antarctica are not predicted by climate models (they assume a slow and linear response to climate forcing – not fast glacier flow).

Glaciers in most parts of the world are rapidly melting and their loss will affect 2 to 3 billion people and valuable paleoclimate archives will be lost forever. Glaciers are our most visible evidence of global warming. They integrate many climate variables in the Earth system. Their loss is readily apparent and they have “no political agenda”. Earth

For Global Climate Change--- Nature is the Time Keeper and none of us can see the clock! • Investments for Global Climate Change • Winners/losers Greed verses fear!

• Some Changes underway: • Conservation • Four cylinders and hybrids sore in popularity • such as: • Fuel cells • Zero emission coal-burning power plants IGCC (Integrated gasification combined cycle) • Solar ie Photovoltaic cells, Passive solar ie. . • Geothermal and recovered energy power plants • Ethanol • power • Mass transit/light rail, buses etc • Housing toward more compact cities • Nanotechnology • LED technology What you can do and safe money! (http://www.climatecrisis.net)

Buy organic foods as much as possible Avoid heavily packaged products Eat less meat Reduce the number of miles you drive Carpool Keep your car tuned up Check your tires weekly to make sure they are properly inflated Choose a fuel efficient vehicle Try car sharing Fly less