I. I.Climate Change – Effects A. A.Sea Level Rise Warming  Ice Melt  Sea Level Rise Increased conversion of ice to water Thermal expansion Since 1880, sea level rising ~15 cm century -1 Accelerated since 1940s Melting of all ice should lead to sea level rise of ~70 m Lomborg – More affluent world should lead to more protection against effects of sea level rise

I. I.Climate Change – Effects B. B.Reduced Ice/Snow Cover Temperate/Tropical glaciers Polar ice caps

Holgate Glacier, AK Muir Glacier, AK 1909 vs vs. 2004

After Dyurgerov and Meier (2005)

SAHFOS

European Space Agency

III. III.Climate Change – Effects C. C.Extreme Weather More and more severe Tropical storms Tornadoes Increasing economic losses Lomborg – Changing population patterns, demography, economic prosperity

I. I.Climate Change – Effects D. D.Precipitation Patterns Warming should lead to Reduced precipitation at low latitudes Increased precipitation at high latitudes Examples Drought in many parts of the world Reduced snowpack in Sierra Nevada Mountains due to rainfall instead of snow Increased agricultural production in some areas Combined with higher temperatures and [CO 2 ]

Source: U.S. Global Change Research Program 20 th Century

Source: U.S. Global Change Research Program

I. I.Climate Change – Effects E. E.Ozone Holes Global warming of the atmosphere translates to stratospheric cooling Stratospheric cooling may enhance ozone destruction in Antarctic and make phenomenon more common in Arctic (Waibel et al. 1999)

I. I.Climate Change – Effects F. F.Ecosystem Effects Expand ranges of warmth-tolerant species and contract ranges of warmth-intolerant species Colder-living species might be displaced poleward as well as upward in elevation Species unable to adapt or move would go extinct Within an ecosystem, some species more sensitive to climate change than others Species composition of communities almost certainly will change Ex: Intertidal (Pacific Grove – Central CA) Significant abundance changes in 32/45 species between 1931 and /9 southern species increased significantly 5/8 northern species decreased significantly Changes in CO 2 concentration  lower pH of ocean Behavioral changes (Ex: Sockeye salmon)

I. I.Climate Change – Effects G. G.Health Consistently elevated temperatures can lead to immunosuppression Exacerbated by elevated levels of UV-B Allergies could worsen due to increased pollen production (heat), dust (drought), mold (humidity) Additional human mortality from severe summer heat

U.S. Global Change Research Program

I. I.Climate Change – Effects H. H.Tropical Pests and Diseases Many tropical diseases transmitted by animal vectors – insects, rodents Concern that global warming could increase geographic ranges of vectors a. a.Dengue fever Ex: 1995 – Rising temperatures allowed a coastal mosquito species to cross mountains and spread across Costa Rica, carrying dengue fever Reached as far north as Texas border 140,000+ people infected; died

I. I.Climate Change – Effects H. H.Tropical Pests and Diseases b. b.Malaria Most prevalent vector-borne disease (1-2 million cases/year) Transmitted by Anopheles mosquitoes Warming could lead to Broader geographic range (estimate that +2 o C could expand range from 42 to 60% of land area) Higher metabolic rate  More food Faster maturation  More rapid reproduction Faster parasite life cycle Potential spread into large urban areas (Nairobi, Kenya; Harare, Zimbabwe) with immunologically naïve pop’ns Projections are controversial and highly variable

Climate Change – Effects