CLIMATE CHANGE – cont. -

What Affects the Earth’s climate???

• The climate system is a complex, interactive system consisting of the

• atmosphere

• land surface

• snow and ice

• oceans and other bodies of water

• and living things

From the 2007 IPCC Working Group 1 Report

From the 2007 IPCC Working Group 1 Report

THE RANGE OF INCREASE IN CARBON DIOXIDE CONCENTRATION BY 2050 WILL BE 450 TO 550 ppm.

THIS WOULD GIVE A RANGE OF INCREASE IN TEMPERATURE FROM 2o F to 5o F.THE UNCERTAINTY IS BASED ON DIRECTIONS THAT WE CHOOSE TO GO.

DURING THE LAST 100 YEARS, THE EARTH HAS WARMED ABOUT 1O C.

SOME OF THE INDICATORS OF THIS LONG TERM TREND INCLUDE:

1. HEAT WAVES AND PERIODS OF UNUSUALLY WARM WEATHER

2. OCEAN WARMING, SEA-LEVEL RISE AND COASTAL FLOODING

3. GLACIERS MELTING

4. ARTIC AND ANTARCTIC WARMING

WEATHER EVENTS:

MOST POWERFUL EL NINO EVER (1997-98)

MOST DEVASTATING HURRICANE IN 200 YEARS (MITCH, 1998)

HOTTEST EUROPEAN SUMMER ON RECORD (2003)

THE FIRST SOUTH ATLANTIC HURRICANE EVER (2002)

THE WORST STORM SEASON EXPERIENCED BY FLORIDA (2004)

IN THE ANTARCTIC THERE HAS BEEN A DECREASE IN SEA ICE BY 20% SINCE 1950.

THE EMPEROR PENGUIN POPULATION HAS DECREASED BY 50%.

THE ADELIE PENGUIN POPULATION HAS DECREASED BY 70%.

LARSEN B ICE SHELF (1,268 SQUARE MILES) COLLAPSED IN A MATTER OF WEEKS IN FEBRUARY 2002.

ARCTIC ICE CAP HAS REDUCED SUMMER EXTENT BY 20% AND THE REMAINING ICE THICKNESS HAS REDUCED BY 40%.

EXPANDING DESERTIFICATION OF THE SAHEL REGION OF AFRICA.

SCIENTISTS FEEL THAT THIS IS A RESULT OF WARMING OF THE INDIAN OCEAN.

THIS HAS RESULTED IN POLITICAL CONFLICTS IN SUB-SAHARAN AFRICA.

“HUMANS FIGHT WHEN THEY OUTSTRIP THE CARRYING CAPACITY OF THEIR ENVIRONMENT. EVERYTIME THERE IS A CHOICE BETWEEN STARVING AND RAIDING, HUMANS RAID.

- STEVEN LEBLANC -

SOME OF THE IMPACTS OF THIS WARMING INCLUDE:

1. SPREADING DISEASE

2. EARLIER SPRING ARRIVAL AND LATER FALL

3. PLANT AND ANIMAL RANGE SHIFTS AND POPULATION CHANGES

4. CORAL REEF BLEACHING

5. DOWNPOURS, HEAVY SNOW FALLS, AND FLOODING

6. DROUGHTS AND FIRES

10 METER RISE IN SEA LEVEL WOULD FLOOD ABOUT 25% OF THE U.S. POPULATION.

http://pubs.usgs.gov/fs/fs2-00/

1941 2004

Riggs Glacier, Alaska

BETWEEN GLACIAL PERIODS AND INTERGALCIAL PERIODS, THERE IS ALSO A LARGE CHANGE IN SEA LEVEL.

20,000 YEARS AGO DURING THE LAST ICE AGE, THE SEA LEVEL WAS 125 METERS LOWER THAN IT IS AT PRESENT.

WE ARE IN AN INTERGALCIAL PERIOD. IN OTHER INTERGLACIAL PERIODS, THE SEA LEVEL HAS BEEN ANYWHERE BETWEEN 3 AND 20 METERS HIGHER THAN PRESENT.

CHANGE IN ICE CAP ON MT. KILIMANJARO.

MEASUREMENTS OF THE GREENLAND ICE SHEET IN 2002 SHOWED 685,000 SQUARE KILOMETERS OF MELT - AN AREA DOUBLE THAT IN 1992.

SINCE 1958, THERE HAS BEEN A 40% LOSS IN SEA ICE VOLUME OF THE ARCTIC ICE SHEET.

THE ARCTIC IS WARMING ABOUT TWICE AS FAST AS THE GLOBAL AVERAGE.

THERE IS A FEEDBACK MECHANISM AT WORK HERE. AS ICE MELTS, LESS RADIATION IS REFLECTED BACK INTO SPACE AND WARMING ACCELERATES.

http://video.on.nytimes.com/?fr_story=aa9ac8c8b71dbc3e2c455b7e6d51020c29c0cd8e

CROSS SECTION OF PERMAFROST

IN THE DISCONTINUOUS PERMAFROST, THE GROUND IS WITHIN 1-2 DEGREES OF MELTING, THE PERMAFROST WILL DISSAPEAR.

THE CONTINUOUS PERMAFROST WILL SEE UPHEAVALS IN THE FREEZING AND THAWING THAT WILL RESULT.

THE ARCTIC HAS 1/3 OF THE WORLD’S STORED CARBON. MUCH OF THIS WOULD BE RELEASED ON THAWING OF THE PERMAFROST.

SUB-ARCTIC WESTERN SIBERIA IS THE WORLD’S LARGEST FROZEN PEAT BOG.

IT CONTAINS HUGE AMOUNTS OF FROZEN METHANE HYDRATE.

METHANE IS A GREEN HOUSE GAS THAT CAN ABSORB 21 TIMES THE AMOUNT OF HEAT AS CARBON DIOXIDE.

Distribution of organic carbon in Earth (excluding dispersed carbon in rocks and sediments, which equals nearly 1,000 times this total amount). Numbers in gigatons (1015 tons) of carbon.

EFFECT OF SPRUCE BARK BEETLES ON THE KENAI PENINSULA.

The Anopheles mosquito, a carrier of many diseases such as malaria, encephalitis, yellow fever and dengue feverPhoto: CDC/James Gathany

WITH WARMING, THE RANGE INCREASES - LATITUDE AND ALTITUDE

THINGS AREN’T GETTING ANY BETTER:

CO2 EMISSIONS GREW AT AN ANNUAL RATE OF 1.1% IN THE 1990’S

FROM 2000 TO 2004, THE ANNUAL GROWTH RATE FOR CO2 WAS 3% - NEARLY TRIPLE THAT FOR THE 1990’S

DEVELOPING NATIONS ACCOUNTED FOR 73% OF THE EMISSIONS GROWTH

NO REGION HAD REDUCED THE PERCENTAGE OF ITS CARBON EMISSIONS

PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES

WHAT IS DRIVING THIS?

MAINLY POPULATION.

IT WAS NOT UNTIL 1830 THAT GLOBAL POPULATION REACHED ONE BILLION.

THE SECOND ONE BILLION TOOK ONLY 100 YEARS.

THE THIRD ONE BILLION TOOK ONLY 30 YEARS.

THE FOURTH ONE BILLION TOOK ONLY 20 YEARS.

THE FIFTH ONE BILLION TOOK ONLY 12 YEARS.

WE ARE ADDING POPULATION AT THE RATE OF 80 MILLION PER YEAR - MOSTLY IN THE POOREST COUNTRIES.

THIS IS A RECIPE FOR MANY BAD THINGS - NONE OF THEM GOOD.

POSSIBLE TIPPING POINTS:

1. CHANGE IN EARTH’S ALBEDO

2. MELTING OF GREENLAND ICE CAP AND CHANGE IN GULF STREAM

3. MELTING OF PERMAFROST AND RELEASE OF CARBON DIOXIDE AND METHANE

4. LOSS OF AMAZON RAIN FOREST