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Source: IPCC
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1.Reduced Biodiversity (rapid change) 2.Sea level rise and coastal flooding (melting ice and thermal expansion) 3.Expansion of tropical disease range 4.Soil Moisture Decreases and Desertification ?
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5.Increased frequency of heat illness (problem for the elderly) 6.Increased frequency of severe events? 7.Engineering problem of thermokarst (transportation and housing) 8.Affect on outdoor winter recreation and winter tourism
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1.Increasing NPP? 2.Increased food production?: CO 2 fertilization, range & growing season (depends on soil moisture/depth/nutrients) 3.Increased water-use efficiency 4.Increased nutrient-use efficiency? 5.High latitude warming (positive and negative)
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Source: IPCC
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Ice core data Temperature, CO 2 and CH 4 are all in phase Are the gas concentrations a cause or an effect of warming or both ?
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Source: IPCC
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HADCM3 Model Prediction Global Circulation Model Projection: Non-uniform spatial distribution of global surface temperature increase
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Free Air Carbon Dioxide Enrichment (FACE)
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FACE Results: NPP increases (eg. 40% in cotton; 25% for Sweetgum for 550 ppm vs. 370 ppm) Carbon sink increase limited for forests: Increase in wood production is short-lived; C goes mainly to fine roots and leaves; affected by soil fertility No effect on LAI Stomatal conductance decreases (increased water-use efficiency) Lower leaf nitrogen concentration: need less or have less?
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Carbon Sinks
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But what are we doing to our sinks ? http://news.bbc.co.uk/2/hi/americas/3609887.stm
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Annual Atmospheric Increase 3.3(±0.2) PgC (billion metric tonnes) Why ? Emissions from fossil fuels +5.5(±0.5) Changes in land use +1.6(±0.7) Oceanic uptake - 2.0(±0.8) Missing carbon sink - 1.8(±1.2) Possible source: Underestimation of terrestrial uptake Mid-latitude forest regrowth ? Will the missing sink last ? Source: Woods Hole Observatory
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Source: IPCC
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Meanwhile, we are detecting stratospheric cooling ! Why ? Ozone depletion Tropospheric [CO 2 ] increases
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Interannual climatic variability at the global scale Caused by changing atmospheric and oceanic circulation in the tropical Pacific Ocean
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See http://www.cdc.noaa.gov/map/clim/sst_olr/sst_anim.shtml
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Q. Is there a relationship between the frequency and/or strength of El Nino Southern Oscillation and climate change ? A. We don’t know. However, effects might be exacerbated in a warmer climate (higher sea levels would enhance flooding, precipitation heavier during enhancement, evaporation greater during drought phases)
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El Nino-related flooding in N. California Mainly due to shifting winds
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