Climate threat:

what has changed, what could change

Gustavo V. Necco

Climate threat:

what has changed, what could change

Gustavo V. Necco

UNICAMP UNICAMP 5 October 2004, Campinas, Brazil5 October 2004, Campinas, Brazil

Carbon dioxide levels rise - Mercury climbsOceans warm – Glaciers melt – Sea level risesSea ice thins – Permafrost thaws – Wildfires increaseLakes shrink – Lakes freeze up later – Drought linger Ice shelves collapse – Precipitation increasesMountain streams run dry – Winter loses its biteSpring arrives earlier - Autumn comes laterPlants flower sooner – Migration times varyBirds nets earlier – Diseases spread Coral reefs bleach – Habitats changeSnow packs decline – Amphibians disappearCoastlines erode - Cloud forest dryTemperature spike at high latitudes

GLOBAL CHANGE? GLOBAL “WARNING”?National Geographic, September 2004

Global Change

“Changes in the global environment (including alterations in the climate, land productivity, oceans or other water resources, atmospheric chemistry, and ecological systems) that may alter the capacity of the earth to sustain life.”

Primary Contributors to the Natural Greenhouse Effect

Water Vapour

OtherCarbon Dioxide

~65%

~25%~10%

Increase in last centuryCarbon dioxide: 30 percent +Methane: 100 percentNitrous oxide: 15 percentHalocarbons: ?

The earth has a natural greenhouse effect due to trace amounts of H20 and CO2 that

naturally occur. The enhanced greenhouse effect refers to the augmentation of these natural gases by human activities

The net result is that we are depositing approximately 2 billion extra tons of carbon in an out of equilibrium cycle. Eventually this will be taken up by the land but the timescale for that process is unknown. Hence, the extra carbon, in the form of C02 remains in the atmosphere.

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G-8

Vostok (Antarctica): 4 glacial cycles

(Petit et al., 1999)

Milankovitch (astronomic) factors

Combined annual land-surface air and sea surface temperature anomalies (°C) 1861 to 2003, relative to 1961 to 1990. Two standard error uncertainties are shown as bars on the annual number.

Hadley Center

Global annual surface temperature anomalies by hemisphere: a) NH, b) SH. Both were calculated with respect to the 1961-1990 period.

BAMS, Vol. 85, N° 6, June 2004

Global annual surface temperature anomalies

Global mean annual temperature over the past 2 millenia

Reconstructions of NH global mean annual temperatures over the past two millennia. Expansion compares a number of different estimates over the past 1000 years. Smoothed (40- year low passed) versions are shown to highlight low-frequency variations.

Jones & Mann, Reviews of Geophysics, Vol. 42, N° 2, June 2004

Global map of temperature anomalies for the 2002 meteorological year (Dec. 2001-Nov. 2002) relative to the 1951-1980 baseline

NASA/GISS

Regional trends of surface temperature minus lower tropospheric temperatures(°C/decade). Surface temperatures are from IPCC (2001) and lower tropospheric temperatures from Christy et al. (2000). UNDERSTANDING RECENT ATMOSPHERIC TEMPERATURE TRENDS AND REDUCING UNCERTAINTIESIn support of Chapter 3 of the Strategic Plan for the Climate Change Science ProgramDraft dated 26 November 2002

Annual global temperature departures(1999 value based on 8 month mean)

World Climate Report

Changes in intense NH winter storms and temperatures correlate well

Africa

Changes in the number of warm days.Dark circles represent warming and white circles cooling.

From Easterling et al., 2003

Trends (% time/decade)

Precipitation has increased in some parts of the world and decreased in others

Trends (%/century) in annual precipitation for 1900-2000

Insert figure

Permafrost (perennially frozen ground)

Permafrost temperatures at depths of 11.5 m and 19.5 m, Murtel Corvatsch (Swiss Alps) 1987-2002 (Harris & Haeberli, 2003)

This image illustrates the rapid thinning of the GreenlandIce Sheet as measured by NASA's Airborne Topographic Mapper.

NASA´s scientific visualization studio

Sea-ice extent

Monthly anomalies (millions of km2) of Arctic and Antarctic sea-ice extent for the period 1973-2001, derived from satellite passive microwave sounder data

(Source: HadlSST1 data set, Hadley Centre, UK Met Office)

Trend : - 2.8 % per decade

Antarctic sea ice decline since the 50s (M.A.J. Curran et all., Science, Vol.302, 14 Nov. 2003)

MSA:Methanesulphonic acid

SIE:Sea ice extent for the80E to 180E sector(satellite derived)

Trend:20% decline in SIEsince about 1950

Time series of annual and seasonal sea ice extent in the Northern Hemisphere, 1901-2003 (Annual values from Vinnikov et al. 1999, seasonal values courtesy of B. Chapman, update from Chapman and Walsh, 1993)

BAMS, Vol. 85, N° 6, June 2004

Sea Ice Extent NH 20th Century

Ice concentrations at their minimum summertime levels. Panels a and b display the average minima recorded during 1979-90 and 1991-2002, respectively. Panel c in 2003. Panel d = difference (b-a)

Average size of ice pack in 1979-90 > 1991-2002 by 12%. The Beaufort Sea has suffered the most substantial reduction of ice.

J. F. Comiso & C.L. ParkinsonPhysics Today, August 2004

1979-90

1991-2002 2003ca b

d=(b-a)d

ICE

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ICE

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Arctic ice, ocean and atmosphere are closely interconnected: a change to one influences the others.

a): One possible feedback loop

b): Some of the key fluxes that affect the Arctic system.

The arrows overlay a satellite-derived map of the perennial ice cover when the cover was least extensive in 2002

J. F. Comiso & C.L. ParkinsonPhysics Today, August 2004

Alberta/BC Provincial Boundary Commission

Athabasca glacier in 1917 and 1986. Climate change could result in significant retreat of large glaciers such as this, and related reduction in downstream water flows, wildlife habitat, and hydroelectricity production

B.H. Luckman

Melting glaciers

Kilimanjaro 1970

Kilimanjaro 2000

Photos: L. Thompson

Ice on Kilimanjaro

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1900 1920 1940 1960 1980 2000 2020

Year

Kilimanjaro 2020?A

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L.Thompson et al. 2002

Global Mean Sea-level Change

Global averaged sea-level change between January 1950 and December 2000 from reconstructions, and the global mean sea-level from the TOPEX/Poseidon satellite altimeter (top panel).

Estimated regional distribution of sea-level rise between January 1950 and December 2000 (bottom panel).

The solid line is 2 mm yr-1, and the contour interval is 0.5 mm yr-1

J. A. Church et al.BAMS, Vol. 85, N° 7, July 2004

Bering Sea

Monthly temperatures anomalies (left) at St. Paul Island as a function of month and year. The base period is 1961-1990.Note the shift towards warmer temperatures both after 1976 and for the previous 4 years,

Concentration (% cover) of sea ice over the southeastern Bering Sea between latitudes 57°N and 58°N (right).

Location chart al lower right

J. E. Overland & P.J. StabenoEOS, Vol. 85, N° 33, 17 August 2004

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Bering Sea

The evolution of depth-averaged sea temperatures from an oceanographic mooring at site M2 (56.8°N, 164°W) for spring and summer in different years (Stabeno et al., 2002)

J. E. Overland & P.J. Stabeno, EOS, Vol. 85, N° 33, 17 August 2004

Bering Sea

Spawning biomass (diamonds) and recruitment (yearly addition in millions of fish to the stock) for representative Bering fish: Greenland turbot and flathead sole.

Data from the National Marine Fisheries Services (North Pacific Fishery Management Council, 2003)

J. E. Overland & P.J. StabenoEOS, Vol. 85, N° 33, 17 August 2004

months

60 65 70 75 80 85 90 95123456789101112

60 65 70 75 80 85 90 95Calanus helgolandicusCalanus finmarchicus

1. Changes in the circulation in the N. Atlantic over the last 50 years has affected biodiversity

1962 1972 1982

C. finmarchicus

C. helgolandicus0%

20%

40%

60%

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100%

1992

2. Biodiversity changes has resulted in species 2. Biodiversity changes has resulted in species replacementsreplacements

3. Replacement of similar species but with different seasonal abundances has dramatic consequences for the dynamics of the food web

Key species in the North Atlantic

Calanus finmarchicus

• Up to 80-90% of copepod biomass, and a major herbivore throughout the sub-arctic North Atlantic.

• Important prey species in both shelf and ocean ecosystems – especially for cod!

• Cod populations (juveniles) dependent upon it as a primary food source

Calanus finmarchicusLong term changes in North Sea abundance

Year

1955 1960 1965 1970 1975 1980 1985 1990 1995

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2 Invasion area dataCPR box 12

Whole North Sea data

Heath et al. 1999. Climate fluctuations and the spring invasion of the North Sea by Calanus finmarchicus. Fisheries Oceanography. 8(1):163-176

Vilcinskas 2000

Fisheries:

GEC deals with the Earth system “in toto”: Ecosphere + the human factor

Ecosphere

Human factor

atmospherecryospherehydrospherelithospherebiosphere

anthropospherehuman decisions and actions

The Earth System: Coupling the Physical, Biogeochemicaland Human Components

/ DIVERSITAS

AtmosphereModels

OceanModels

Land SurfaceModels

TerrestrialBiosphere

Models

Solid Earth

Models

Car

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The Earth SystemUnifying the Models

The Predictive Earth System

Megaflops Gigaflops Teraflops Petaflops

Natural HazardPrediction

Hydrology

ProcessModels

Climate / WeatherModels

2000 2010

Coupling AGCMs to OGCMs is a complex process

IPCC, TAR, 2001

Comparison between modeled and observations of temperature rise since 1850

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Adaptation -Sustainability

Survival

IPCC Projections2100 AD

Abrupt change

• In nonlinear complex systems, minute actions can cause long term, large scale changes. These changes can be abrupt, devastating, surprising, unmanageable.

Abrupt change

. Large and rapid – ocurring faster than say a few decades.

The term abrupt implies not just rapidity but also reaching a breaking point: a threshold – it implies a change that does not smoothly follows the forcing, but it is rapid in comparison to it.

Abrupt climate change = strong non-linear response to the forcing

The change from winter to summer, a very large change occurring within six months (in many places larger than the glacial-interglacial transition), it is not an abrupt change in climate (or weather), it is rather a gradual transition following the solar forcing in its near-sinusoidal path.

Time Time

ThresholdResponseForcing

Response

Forcing

Denser waters in high latitude oceans create a thermohaline circulation (THC) system that has a major impact on regional climates

Steady-state solutions of the two-box model as a function of the atmosphere-ocean freshwater flux. Paths along the solution curves of two versions of Stommel’s box model showing the rate of the ocean overturning when the freshwater forcing flux H is increased and then decreased. Only in the case of weak diffusion (orange) does the model respond with an abrupt change, once a threshold in H is crossed.

Change in the strength of the North Atlantic meridional overturning circulation (svds) in a number

of simulations with increases in greenhouse gases

Source: Cubasch et al. 2001

(pe

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Age (kyr before present)

Dansgaard-Oeschger (warm) events and Heinrich (cold) events

(Above) Record 18O from the GRIP (Greenland Ice Sheet Project) ice core, a proxy for atmospheric temperature over Greenland. Note the stable Holocene climate during the past 10000 years and before that the much colder glacial climate punctuated by D-O warm events (numbered). The time of Heinrich events is marked with black dots. Garnopolski & Rahmstorf, 2001

(Right) Sea surface temperature derived marine sediments in the Subtropical Atlantic (Bermuda Rise) compared to 18O values from the GISP2 core in Greenland

“You will be swept away by sights you’ll never be able to see on the Weather Channel”

- Chris Vognar, Daily Morning News

“A big-weather disaster movie designed to put the fear on God into audiences with Olympic stamina and peanut-sized brains”

-James Christopher, Times of London

“You can finally say this about the notion that everybody talks about the weather, but nobody does anything about it: … Roland Emmerich has done something about it. Something stupid, but still … something”

- Stephen Hunter, Washington Post

“This is a doomsday scenario: it feeds paranoid schizophrenia”- Andrew Weber, University of Victoria, Scholl of Earth and Ocean Sciences

 “My first reaction was “Oh my God, this is a disaster because it is such a distortion of the science””

- Dan Schrag, Harvard University, Paleoclimatologist

“Global warming is no joke, but this is pretty silly stuff”-Jay Boyar, Orlando Sentinel

Quoted at BAMS, Vol. 87, N° 7, July 2004

The day after …

THE DAY AFTER TOMORROW

• The Larsen B ice shelf breaks up (this did happen in the real world)

Some comments on

THE DAY AFTER TOMORROW

• The world of climate science – labs, groups, scientists (OK)

• UN Climate conference in Delhi + politics of climate change (reaction of Vice-president in the film) (OK)

• Melt water inflow halting the North Atlantic current and causing severe cooling in a matter of days (????)

• A few super giant (tropical type) cyclones covering the entire NH causing flooding, hail, tornados, etc. (????)

• Cold air from the eyes of the super-cyclones sucked-down from the upper troposphere to the surface and shock-freezes the sky-scrapers (????)

• Flooding of Manhattan produced by a wind-driven “tsunami” (????)

• The “hero” is a climatologist (OK – it stirs the interest of the public for the subject)

Inpired by Stefan Rahmstorf, 2004

Critical regions

Schellnhuber,2002

Critical region analysis of hot spots or switch and choke points: an early attempt at identifying parts of the Earth where changes at regional scales can cause significant changes in the functioning of the Earth system as a whole. Perturbations to the system may trigger abrupt changes, either repeating conditions that have existed in the past, or even causing shifts to new modes of operation.

“Greenhouse skeptics” or “climate contrarians”

Many newspapers have commented on cold spells in recent years, implying they weaken the case for global warming. Global warming refers to a long-term trend. Short-term events are interesting but have no bearing on the problem.

A small group of vocal scientists (known collectively as “climate contrarians” or “greenhouse skeptics”) keep emphasizing the well-known uncertainties in all climate assessment. The climate change debate buzzes along, with the "not proven" minority asserting that we are in the grip of a mass panic, led by the world's climate scientists. Tasmanian John Daly, for instance, argues the debate is caused by sheer professional aggrandisement, "advancing the interests of what was a small academic discipline 30 years ago to become a mammoth global industry today".

• Dr. S. Fred Singer, physicist and former director of the U.S. Weather Satellite Service, issued the following warning,  The United States and other industrialized nations are on the brink of adopting policies that will ruin national economies, and drive manufacturing and other industries into less developed and less regulated countries ... all to mitigate "disasters" that exist only on computer printouts and in the feverish imagination of professional environmental zealots.

• Dr. Frederick Seitz, President Emeritus of Rockefeller University. A physicist a recipient of the National Medal of Science and a past President of both the National Academy of Sciences and the American Physical Society. The Wall Street Journal (WSJ) published his article "A Major Deception on Global Warming." on June 12, 1996, just days after formal release of the IPCC SAR and scant weeks before the COP-2 meeting in Geneva,

• Dr. Bjorn Lomborg (“the scourge of the greens”), currently the director of Denmark's Environmental Assessment Institute, is the author of "The Skeptical Environmentalist", 2001, a global bestseller that claimed a systematic exaggeration of the Earth's environmental problems. Environmentalists brought a complaint about the book before a body called the Danish Committees on Scientific Dishonesty (DCSD), which declared that Dr Lomborg's book was "contrary to the standards of good scientific practice," By end 2003 the Danish Ministry of Science repudiated the findings. Critics to the book by American scientists were published by Scientific American in January 2002 sparking a passionate controversy. Dr Lomborg claims that proposed economic measures to counteract climate change are too expensive.

“Greenhouse skeptics” or “climate contrarians”

• Professor Richard Lindzen, Alfred P. Sloan Professor of Meteorology, working in the department of Earth, Atmospheric and Planetary Science at Massachusetts Institute of Technology. Professor Lindzen believes that the climate models used by the Intergovernmental Panel on Climate Change do not properly account for the physics of cloud formation, and that as a result they exaggerate the warming effect of CO2. (Failing to take into account the “iris effect”).

Prominent skeptics organizations

• Global Climate Coalition <http://www.globalclimate.org>Founded in 1989 by 46 corporations and trade associations representing all major elements of US industry, the GCC presents itself as a "voice for business in the global warming debate.“ It has been deactivated but the webpage is still on.Arguments: Global Warming is real, but it is too expensive to do anything about. The Kyoto Protocol is fundamentally flawed.Funding: Corporate members (industries, trade associations etc.). British Petroleum, Daimler Chrysler, Texaco and General Motors left the coalition.

• George Marshall Institute  <http://www.marshall.org>This conservative think tank has published numerous reports downplaying the severity of global climate change. It was very influential in the Bush Sr. Administration’s climate change policy..Arguments: Blame the Sun. The Kyoto Protocol is fatally flawed.Affiliated Individuals: Robert Jastrow, ex-Director of NASA's Goddard Institute for Space Studies ; and Frederick Seitz.

• Oregon Institute of Science and MedicineThe Marshall Institute co-sponsored with the OISM a deceptive campaign -- known as the Petition Project -- to undermine and discredit the scientific authority of the IPCC and to oppose the Kyoto Protocol in 1998. The Petition resurfaced in 2001.Arguments: There is no scientific basis for claims about global warming. IPCC is a hoax. Kyoto is flawed.Funding: Petition was funded by private sources.Affiliated Individuals: Arthur B. Robinson, Sallie L. Baliunas, Frederick Seitz

Prominent skeptics organizations (cont.)

• Science and Environmental Policy Project (SEPP) <http://www.sepp.org>Founded in 1990 by widely publicized climate skeptic S. Fred Singer, SEPP’s stated purpose is to "document the relationship between scientific data and the development of federal environmental policy."Arguments: Climate change won t be bad for us anyway. Action on climate change is not warranted because of shaky science and flawed policy approaches.Funding: Conservative foundations including Bradley, Smith Richardson, and Forbes (Sung Myung Moon s Unification Church ?),.Affiliated Individuals: S. Fred Singer,Frederick Seitz, Bruce Ames.

• Greening Earth Society <http://greeningearthsociety.org>The Greening Earth Society (GES) was founded on Earth Day 1998 by the Western Fuels Association to promote the view that increasing levels of atmospheric CO2 are good for humanity.. The Western Fuels Association (WFA) is a cooperative of coal-dependent utilities in the western states that works in part to discredit climate change science and to prevent regulations that might damage coal-related industries. On March 9, 2004, GES distributed a Newsletter claiming “Snow fooling!:Mount Kilimanjaro’s glacier retreat is not related to global warming” citing a paper in the International Journal of Climatology (the paper asserted that Kilimanjaro’s ice was shrinking because East Africa’s climate is drying, a process that began more than a century ago).. Arguments: CO2 emissions are good for the planet; coal is the best energy source we have.Funding: The Greening Earth Society receives its funding from the Western Fuels Association, which in turn receives its funding from its coal and utility company members.Affiliated Individuals: Patrick Michaels, Robert Balling, David Wojick, Sallie Baliunas, Sylvan Wittwer, John Daley, Sherwood Idso

• Competitive Enterprise Institute CEI <http://www.cei.org>The Competitive Enterprise Institute claims to be a non-profit public policy organization dedicated to the principles of free enterprise and limited government. Since its founding in 1984, CEI has grown into a $3,000,000 institution with a team of nearly 40 policy experts and other staff. Coined the term "free-market environmentalism“. In 1995 the Wall Street Journal labeled CEI "the best environmental think tank." Arguments: Market institutions more effectively allow for the realization of environmental values than political agencies and bureaucracies. The Kyoto treaty would devastate the economies of the industrialized world. Climate change is based on uncertain science and bad economics. Ideologically driven: strongly attacks “green-reds” (“eco-socialists”) and “environmental alarmists”.Funding: CEI does not publish a list of its institutional donors. Known contributors : ExxonMobil, Coca Cola, Texaco, FMC Foundation, General Motors, Pfizer Inc..Affiliated Individuals: William Dunn (Chair Board of Directors), Fred L. Smith, Jr. (President and Founder), Myron Ebell (Director of Global Warming and International Environmental Policy, he also chairs the Cooler Heads Coalition ).

Prominent skeptics organizations (cont.)

• Center for the Study of Carbon Dioxide & Global Change <http://www.CO2science.org>The Center claims to "disseminate factual reports and sound commentary on new developments in the world-wide scientific quest to determine the climatic and biological consequences of the ongoing rise in the air's CO2 content." The Center is led by two brothers, Craig and Keith Idso. Their father, Sherwood Idso, is affiliated with the Greening Earth Society.Arguments: Increased levels of CO2 will help plants, and that's good.Funding: The Center is extremely secretive of its funding sources.Affiliated Individuals: Craig Idso, Keith Idso, Sylvan Wittwer

Those who stand away from the climate consensus often cite the following points:

• Computer modeling is unreliable. For example, the models do not resolve small-scale processes, such as local atmospheric convection. In addition, it is difficult to integrate processes that operate on different time-scales – as when the models try to couple the atmosphere to the ocean.

Better models

• Atmospheric physics is not well understoodLargely due to our gaps in understanding of how the climate system deals with cloud feedback .

More research

More (climatic & paleo climatic) data + appropriate statistical tools

• Climate reconstruction is unreliableSince it is done, in part, by incorporating statistical behavior of questionable reliability.

Ultimately, however, these competing levels of concern – which have their basis in geography, politics and economics – should not be allowed to get in the way of the strictly scientific question: Is the Earth warming and are anthropogenic greenhouse gas emissions to blame? And, if so, what consequences are to be expected for further warming?

What’ s the problem here?

Extreme, maximalist, attitudes and approaches

“Panglossian” vs. “Catastrophic” scenarios

“Good-for-you” vs. “End-of-the-world”

The two lowest probability cases in climate change (Stephen H. Schneider)

References

• Science & impact of climate change presentation graphics Meteorological Service of Canadawww.msc.ec.gc.ca/education/scienceofclimatechange/understanding

• Climate change: what we know and what we need to know Royal Meteorological Society, August 2002

www.royalsoc.ac.uk

• ”The discovery of global warming”

Spencer Weart, July 2004www.aip.org/climate

• “Abrupt Climate Change: Inevitable surprises”National Research Council, 2002

http://books.nap.edu/books/0309074347/html/index.html

www.iai.intwww.iai.int