Why it Matters  You know that CO2 levels in the atmosphere are higher now than anytime in over 500,000 years.  You know CO2 and global temperatures are directly linked.  What you may not know is why a warmer world is a more dangerous and difficult world to live in.

Consequence #1: Sea Ice Melt  As sea ice of the Arctic and Antarctic melts, it causes several problems:  Loss of habitat for polar organisms  Increased iceberg danger to shipping  Increased conflict over potential resources

Habitat loss for polar animals Polar Bears: Threatened with Extinction

Icebergs: bad for Ships A flotilla of hundreds of icebergs that split off Antarctic ice shelves is drifting toward New Zealand and could pose a risk to ships in the South Pacific, officials said Tuesday. The nearest one, about 90 feet tall, was 160 miles southeast of Stewart Island, said Neal Young, an Australian glaciologist. Ice shelves have routinely sloughed off icebergs, but he said the rate appeared to be increasing as a result of regional warming in Antarctica. He said he counted 230 icebergs in two satellite images alone.New Zealand

Conflict Over a New Sea

Consequence #2: Land Ice Melt  The melting of glaciers and ice sheets have serious implications:  Sea level rise  Water shortages  Permafrost melt

Sea Level Rise  The melting of land ice, like that of Greenland and Antarctica, adds to the volume of water in the Ocean.

Sea Level Rise

Sea-level Refugees: Up to 150 Million by 2050

Glacier Melt Water Shortage  Over 1 billion people depend on freshwater from glaciers during some or all of the year.  If temperatures rise by 4 o C by 2100, glaciers will be history… along with the rivers they supply.

Permafrost melt  Permafrost is land that is permanently frozen… or was…

Consequence #3 Ocean Acidification  CO2, when dissolved in sea water, can produce carbonic acid, H2CO3.  As CO2 increases in the atmosphere, the pH of the oceans decreases

Acidification Problems  Lower pH has devastating effects of some organisms:  Coral organisms die  Mollusks cannot make carbonate shells

Consequence #4 Severe Weather  Global warming is correlated with increased frequency and/or severity of:  Floods / heavy rains  Tropical storms  Droughts  Heat waves

Consequence #5: Desertification  Desertification is the expansion of existing deserts to cover larger areas. It has accelerated in line with global warming

Desertification Problems  Biodiversity loss.  Infrastructure destruction.  Lost agricultural productivity.  Water shortage.

Consequence #6 Increased Forest Fires

Consequence #7: Increased Range of Disease  As temperatures warm, tropical diseases increase their range.

Consequence #8: More Global Warming  Many of the consequences cause even more warming, in a vicious POSITIVE FEEDBACK CYCLE.  Fires cause more CO2 in the atmosphere.  Melting sea ice no longer reflects sunlight.  Melting permafrost releases greenhouse gases.