introduction to global warming jagadish shukla center of ocean-land- atmosphere studies lecture 5:...

Introduction to Global WarmingIntroduction to Global Warming

Jagadish ShuklaJagadish Shukla

Center of Ocean-Land-Atmosphere studies

Lecture 5: Sep 15, 2009

CLIM 101: Weather, Climate and Global Society

HumansEcosystems

WeatherClimate


Global Well-Being (sustainability, security

and the future of civilization)

The Global ChallengeThe Global Challenge

Inequality and Extreme Poverty

Human PopulationGrowth

EnvironmentalDegradation



World PopulationWorld PopulationWorld Population from AD 1 to 2002

Source: Data from Maddison (2001), Calculated using data from Maddison (2002)

World Income from 1500 to 2001

World Income per Capita from 1500 to 2001

Since 1750, population increased 10 times; Production per person also increased 10 times; Therefore, total world economic production increased 100 times.

Therefore, the impact of human activity on life-sustaining system on earth increased enormously.

Planet under StressPlanet under Stress

‘Common Wealth’ by Jeffrey Sachs, 2008


Global PovertyGlobal Poverty

‘Common Wealth’ by Jeffrey Sachs, 2008

From 1820 to 1992

Examples of Short-Term Climate Variability


1998 JFM SST [oC]

JFM SST Climatology [oC]

1998 JFM SST Anomaly [oC]

El Nino/Southern OscillationEl Nino/Southern Oscillation


Summer 2003 European Heat Wave: Summer 2003 European Heat Wave: Result of Global Warming? Result of Global Warming?

• The immediate cause of the heat-wave was a persistent high pressure center over Northwest Europe.

• There is currently no evidence that human influence on climate makes such circulation patterns more likely.

Summer 2003 temperatures relative to 2000-2004

LAST CENTURY OR SO …LAST CENTURY OR SO …


Monthly Mean Carbon DioxideMonthly Mean Carbon DioxideNOAA CMDL Carbon Cycle Greenhouse GasesNOAA CMDL Carbon Cycle Greenhouse Gases


Atmospheric carbon dioxide mixing ratios determined from the continuous monitoring programs at the 4 NOAA CMDL baseline observations. Principal investigator: Dr. Pieter Tans. NOAA CMDL Carbon Cycle Greenhouse Gases. Boulder, Colorado. (303) 497-6678


LAST LAST TWO MILLENIATWO MILLENIA OR SO … OR SO …

2000 Year Northern Hemisphere Reconstruction of Surface Air Temperatures2000 Year Northern Hemisphere Reconstruction of Surface Air Temperatures

Tem

per

atu

re A

nom

aly

(oC

)

What’s Happening in the Upper Atmosphere?What’s Happening in the Upper Atmosphere?


The Climate of a Planet Depends On …The Climate of a Planet Depends On …1. Energy from the Sun

(energy from the interior)

2. Planetary Albedo

3. Speed of Planet’s Rotation

4. Mass of the Planet

5. Radius of the Planet

6. Atmospheric Composition

7. Ocean-Land, Topography

S

M

a

H2O, CO2, O3, clouds

h*


Earth’s Energy BalanceEarth’s Energy Balance

Solar Radiation

S = 1380 Wm-2

(plane, parallel)

Assume radiative equilibrium, so that

INCOMING ENERGY = OUTGOING ENERGY

Measured albedo () = 0.31Measured planetary E = 237 Wm-2

Implied TE = 255 K

Measured surface Es = 390 Wm-2

Atmosphere absorbs 153 Wm-2

Measured Ts = 288 K

Planetary Emission

Ts (288K) > Te (255K) … Greenhouse Effect (H2O, CO2)Life on planet Earth!

WarmingWarming

1. Greenhouse gases (CO1. Greenhouse gases (CO22, CH, CH44, N, N22O)O)• CO2: Carbon Dioxide : Emission from fossil fuel• CH4: Methane : Agriculture• N2O: Nitrous Oxide

2. Land use change2. Land use change

CoolingCooling

1.1. AerosolsAerosols• Man made/Natural• Volcanoes

※※Rate of increase of GHG is largest in 10,000 yearsRate of increase of GHG is largest in 10,000 years

(Net) Global Warming (Net) Global Warming


Recent analyses of satellite measurements do not indicate a long-term trend in solar irradiance (the amount of energy received by the sun), Frohlich and Lean (2005)


Solar IrradianceSolar Irradiance


Greenland Grace monthly mass solutions. For the entire Greenland ice sheet, for April 2002 to April 2006, after scaling the results and removing the mean. The blue error bars include only the contributions from uncertainties in the GRACE gravity fields. Velicogna and Wahr (2006)

Greenland Ice MassGreenland Ice Mass

Thanks: R. Cicerone


Carbon CycleCarbon CycleCurrent Global Carbon Cycle (2000-2005)Current Global Carbon Cycle (2000-2005)

Pools of carbon are in Gt and annual fluxed in Gt C y-1. Background or pre-anthropogenic pools and fluxes are in black. The human perturbation to the pools and fluxed are in red. (updated from Sabine et al. 2004)


CO2 emissions (Gigatons of Carbon, Gt C), IPCC 20071990: 6.4 Gt C (=23.5 Gt CO2 ), 2000-2005: 7.2 Gt C (=26.4 Gt CO2)


Net CO2 FluxNet CO2 Flux

Takahashi et al. 2002

Changes in Greenhouse GasesChanges in Greenhouse Gases


From Ice Age to Modern DataFrom Ice Age to Modern Data


Sea Level Rise over the Last CenturySea Level Rise over the Last Century

Climate Change, 1995


Greenland Grace monthly mass solutions. For the entire Greenland ice sheet, for April 2002 to April 2006, after scaling the results and removing the mean. The blue error bars include only the contributions from uncertainties in the GRACE gravity fields. Velicogna and Wahr (2006)

Greenland Ice MassGreenland Ice Mass

Thanks: R. Cicerone


Figure 3.2Annual Annual AAnomalies of nomalies of Global TemperatureGlobal Temperature

RRelative to the 1961 elative to the 1961 to 1990 meanto 1990 mean

What’s Happening in the Ocean?What’s Happening in the Ocean?

Figure 3.3


Anomaly time series Anomaly time series TThe US Historical Climatology Network (USHCN) datahe US Historical Climatology Network (USHCN) data

full US Historical Climatology Network (USHCN) data

the USHCN data without the 16% of the stations with populations of over 30,000 within 6 km in the year 2000

RRelative to the 1961 to 1990 meanelative to the 1961 to 1990 mean

Center of Ocean-Land-Atmosphere studies FAQ 3.1, Figure 1


Linear Linear TTropospheric ropospheric TTemperature emperature TTrends rends (°C per decade) for 1979 to 2005(°C per decade) for 1979 to 2005


GGlobal lobal MMean ean SSea ea LLevelevel

RRelative to the 19elative to the 198080 to to 19991999 mean mean

Figure 4.2


NH Average Snow-Covered Area (SCA)NH Average Snow-Covered Area (SCA)

1979

Annual Minimum Sea Ice Extent (DMSP

SSM/I)

Shrinking Sea Ice Shrinking Sea Ice Extent in Arctic:Extent in Arctic: Result of Global Result of Global Warming? Warming?

• High latitudes more vulnerable• Ice-albedo feedback• Perennial sea ice shrinking

9.6% per decade since 1979

2005

Great Natural Disasters Great Natural Disasters 1950 – 20051950 – 2005

Number of eventsNumber of events

0

2

4

6

8

10

12

14

16

1950 1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005

Others (Heat wave, cold wave, forest fire)

Flood

StormEarthquake/tsunami, volcanic eruption

© 2006 NatCatSERVICE, Geo Risks Research, Munich Re


Wagner, 2002

U. S. Flow of Raw Materials U. S. Flow of Raw Materials by weight 1900-2000by weight 1900-2000

The use of raw materials in the U. S. increased dramatically during the last 100 years

Emanuel, Nature, 2005

Probability Shifting Toward Probability Shifting Toward Stronger Stronger Tropical CyclonesTropical Cyclones

See http://wind.mit.edu/~emanuel/anthro2.htm for FAQ about hurricanes and global climate change

Power Dissipitation Index (PDI) - A measure of the total power dissipated annually by tropical cyclones in the North Atlantic compared to September sea surface temperature. Note that total Atlantic hurricane power dissipation has more than doubled in the past 30 years.

http://wind.mit.edu/~emanuel/anthro2.htm

• CO2 emissions have grown by 80% between 1970 and 2004.CO2 emissions have grown by 80% between 1970 and 2004.(2005: 379 ppm; All GHG: 455 ppm (CO2 equivalent); Primary reason: fossil fuel use and land-use change)

• Rate of increase of CORate of increase of CO22, CH, CH44, N, N22O was the largest in 10,000 years.O was the largest in 10,000 years.

• Aerosols have partly offset the warming by COAerosols have partly offset the warming by CO22..

• Global mean surface temp. increase (linear trend) 0.76Global mean surface temp. increase (linear trend) 0.76ooC in 100 C in 100 years (1906-2005).years (1906-2005).

• Eleven of the past twelve years are the warmest on record.Eleven of the past twelve years are the warmest on record.

• In the past 500 years, the warmest 50 years were 1951-2000.In the past 500 years, the warmest 50 years were 1951-2000.

The Knowns (Observed)The Knowns (Observed)


• Sea level has risen 1.8 mm/yr since 1961; 3.1 mm/yr since 1993.Sea level has risen 1.8 mm/yr since 1961; 3.1 mm/yr since 1993.

• Arctic sea ice extent reduced by 2.7% per decade since 1978.Arctic sea ice extent reduced by 2.7% per decade since 1978.(The summer minimum on record; 2007)

• Enhanced run-off and earlier spring peak discharge in many Enhanced run-off and earlier spring peak discharge in many glaciers and snow-fed rivers.glaciers and snow-fed rivers.

• Extreme hot nights have increased ; frost days have decreased.Extreme hot nights have increased ; frost days have decreased.

• Earlier timing of spring events (blooms) on land.Earlier timing of spring events (blooms) on land.

• Poleward and upward shifts in plant and animal ranges.Poleward and upward shifts in plant and animal ranges.

• Changes in algal, plankton, and fish abundances (~Temp.).Changes in algal, plankton, and fish abundances (~Temp.).

• Increase in the acidity of oceans.Increase in the acidity of oceans.

The Knowns (Observed)The Knowns (Observed)


THANK YOU!

ANY QUESTIONS?


Introduction to Global WarmingIntroduction to Global Warming

Jagadish ShuklaJagadish Shukla


Lecture 6: Sep 17, 2009

CLIM 101: Weather, Climate and Global Society

IPCC has been established by WMO and UNEP to assess scientific, technical IPCC has been established by WMO and UNEP to assess scientific, technical and socio- economic information relevant for the understanding of climate and socio- economic information relevant for the understanding of climate change, its potential impacts and options for adaptation and mitigation.change, its potential impacts and options for adaptation and mitigation.

IPCC has been established by WMO and UNEP to assess scientific, technical IPCC has been established by WMO and UNEP to assess scientific, technical and socio- economic information relevant for the understanding of climate and socio- economic information relevant for the understanding of climate change, its potential impacts and options for adaptation and mitigation.change, its potential impacts and options for adaptation and mitigation.

Intergovernmental Panel Intergovernmental Panel on Climate Change (IPCC)on Climate Change (IPCC)

Working Group I: The Physical Science Basis

Working Group II: Impacts, Adaptation and Vulnerability

Working Group III: Mitigation of Climate Change


• Largest number of U.S. scientists: nominated by the U.S. Govt.Largest number of U.S. scientists: nominated by the U.S. Govt.

• Highest skepticism : “U.S. Govt.”Highest skepticism : “U.S. Govt.”

• Equations of motions and laws of thermodynamics to predict rate of change of:

T, P, V, q, etc. (A, O, L, CO2, etc.)

• 10 Million Equations: 100,000 Points × 100 Levels × 10 Variables

• With Time Steps of: ~ 10 Minutes

• Use Supercomputers

What is a Climate Model?What is a Climate Model?

• Geographic resolution characteristic of the generations of climate models used in the IPCC Assessment Reports: FAR (IPCC, 1990), SAR (IPCC, 1996), TAR (IPCC, 2001a), and AR4 (2007).

• The figures above show how successive generations of these global models increasingly resolved northern Europe. These illustrations are representative of the most detailed horizontal resolution used for short-term climate simulations.

• The century-long simulations cited in IPCC Assessment Reports after the FAR were typically run with the previous generation’s resolution. Vertical resolution in both atmosphere and ocean models is not shown, but it has increased comparably with the horizontal resolution, beginning typically with a single-layer slab ocean and ten atmospheric layers in the FAR and progressing to about thirty levels in both atmosphere and ocean.


Global mean, volume mean ocean Global mean, volume mean ocean temperaturetemperatureCourtesy of Tom Delworth (GFDL)

GFDL Model Simulations

Courtesy of UCAR

1.0º C



Mean of 15 Models Surface Air Temperature Mean of 15 Models Surface Air Temperature DifferenceDifference(Sresa1b YR 71-100) minus (20c3m 1969-98), Global Average = (Sresa1b YR 71-100) minus (20c3m 1969-98), Global Average =

2.612.61


Climate Model Fidelity and Projections of Climate ChangeJ. Shukla, T. DelSole, M. Fennessy, J. Kinter and D. Paolino

Geophys. Research Letters, 33, doi10.1029/2005GL025579, 2006


Global Global and Continental Temperature and Continental Temperature ChangeChange

Comparison of observed continental- and global-scale changes in surface temperature with results simulated by climate models using natural and anthropogenic forcings. Decadal averages of observations are shown for he period 1906-2005 (black line) plotted against the centre of the decade and relative to the corresponding average for 1901-1950. Lines are dashed where spatial coverage is less than 50 %. Blue shaded bands show the 5-95% range for 19 simulates form 5 climate models using only the natural forcings due to solar activity and volcanoes. Red shaded bands show the 5-95% range for 58 simulations from 14 climate models using both natural and anthropogenic forcings.

AOGCM Projection of Surface TemperaturesAOGCM Projection of Surface Temperatures



Projection of PrecipitationProjection of Precipitation

• Limits of deterministic predictionLimits of deterministic prediction(attribution of an event (Katrina) is not possible)

• No model can explain the past 50 year observed global warming No model can explain the past 50 year observed global warming without increase in the green house gases (GHG).without increase in the green house gases (GHG).

• Sun and volcanoes would have produced cooling.Sun and volcanoes would have produced cooling.

• There is no mechanism known to scientists that can explain the There is no mechanism known to scientists that can explain the global structure of warming in the A, O, L without GHG.global structure of warming in the A, O, L without GHG.

• Warming and sea level rise would continue for centuries, even if Warming and sea level rise would continue for centuries, even if GHG were stabilized. GHG were stabilized.

• Increase in the frequency of heat waves and heavy precipitation.Increase in the frequency of heat waves and heavy precipitation.

• Entire disappearance of arctic late summer sea ice ( ~ 2100 ).Entire disappearance of arctic late summer sea ice ( ~ 2100 ).

The Knowns (Models)The Knowns (Models)


THANK YOU!

ANY QUESTIONS?


introduction to global warming jagadish shukla center of ocean-land- atmosphere studies lecture 5:...

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result of global warming

global povertycommon

thatincoming energy

greenhouse gases co2

planet earth

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world income

greenhouse effect h2o