Reflected Solar Incoming 235 Outgoing 107 Radiation 342 Solar Longwave 107 Wm − 2 Radiation Radiation Global warming 342 Wm − 2 235 Wm − 2 Reflected by Clouds, Aerosol and 77 40 Atmosphere Emitted by Atmospheric 77 Atmosphere 165 30 Window Greenhouse Absorbed by Gases Atmosphere 67 Latent 24 78 Heat 324 40 350 Back Reflected by Radiation Surface 30 390 168 24 78 Surface http://www.ipcc.ch/ Absorbed by Surface Thermals Evapo- 324 Radiation transpiration Absorbed by Surface Figure 1.2: The Earth’s annual and global mean energy balance. Of the incoming solar radiation, 49% (168 Wm − 2 ) is absorbed by the surface. That heat is returned to the atmosphere as sensible heat, as evapotranspiration (latent heat) and as thermal infrared radiation. Most of this radiation is absorbed by the atmosphere, which in turn emits radiation both up and down. The radiation lost to space comes from cloud tops and atmospheric regions much colder than the surface. This causes a greenhouse effect. Source: Kiehl and Trenberth, 1997: Earth’s Annual Global Mean Energy Budget, Bull. Am. Met. Soc . 78, 197-208. Most important Carbon dioxide greenhouse agents Water vapor burning fossil fuel "#$%&'( )*+( ),,+(!-'&$.(/0123'&(454(67%&8'9( Carbon dioxide deforestation Methane Table 1. Summary of Carbon Dioxide Emissions and Net Generation in the United States, 1998 and 1999 Percent Methane 1999 p 1998 Change Change Carbon Dioxide (thousand metric tons) a . . . . . . . Coal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1,799,762 1,787,910 -11,852 -0.66 Petroleum . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110,244 106,294 -3,950 -3.58 Gas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 291,236 337,004 45,768 15.72 Other Fuels b . . . . . . . . . . . . . . . . . . . . . . . . . . 13,596 13,596 U.S. Total . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2,214,837 2,244,804 29,967 1.35 Generation (million kWh) Landfills, cows Coal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1,873,908 1,881,571 7,663 0.41 Petroleum . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126,900 119,025 -7,875 -6.21 Gas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 488,712 562,433 73,721 15.08 Other Fuels b . . . . . . . . . . . . . . . . . . . . . . . . . . Termites 21,747 21,749 2 Total Fossil-fueled . . . . . . . . . . . . . . . . . . . . 2,511,267 2,584,779 73,512 2.93 Nonfossil-fueled c . . . . . . . . . . . . . . . . . . . . 1,105,947 1,106,294 347 0.03 U.S. Total . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3,617,214 3,691,073 73,509 2.04 .... Output Rate d (pounds CO 2 per kWh) Coal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.117 2.095 -0.022 -1.04 Petroleum . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.915 1.969 0.054 2.82 Gas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.314 1.321 0.007 0.53 Other Fuels b . . . . . . . . . . . . . . . . . . . . . . . . . . 1.378 1.378 U.S. Average . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.350 1.341 -0.009 -0.67 a One metric ton equals one short ton divided by 1.1023. To convert carbon dioxide to carbon units, divide by 44/12. b Other fuels include municipal solid waste, tires, and other fuels that emit anthropogenic CO 2 when burned to generate electricity. Nonutility data for 1999 for these fuels are unavailable; 1998 data are used. c Nonfossil includes nuclear, hydroelectric, solar, wind, geothermal, biomass, and other fuels or energy sources with zero or net zero CO 2 emissions. Although geothermal contributes a small amount of CO 2 emissions, in this report it is included in nonfossil. d U.S. average output rate is based on generation from all energy sources. P = Preliminary data. = No change. Note: Data for 1999 are preliminary. Data for 1998 are final. Sources: Energy Information Administration, Form EIA-759, “ Monthly Power Plant Report ” ; Form EIA-767, “ Steam-Electric Plant Operation and Design Report ” ; Form EIA-860B, “ Annual Electric Generator Report Nonutility ” ; and Form 900, “ Monthly Nonutility Power Report. ” Federal Energy Regulatory Commission, FERC Form 423, “ Monthly Report of Cost and Quality of Fuels for Electric Plants. ”
NEWS Nature Published online: 28 November 2006; | doi:10.1038/444524a Methane quashes green credentials of hydropower Emissions from tropical dams can exceed fossil-fuel plants. Perhaps 100 million ton of methane produced by (3?) tropical dams (in Brazil?), a sizable contribution to global warming. Ozone layer - Increase of UVB CFC - ChloroFluoroCarbons (regulated since 1987) NOx - contributes also to greenhouse effect (a) Annual temperature trends, 1901 to 2000 (b) Annual temperature trends, 1910 to 1945 Consequences Increase in temperature sea surface temperature (c) Annual temperature trends, 1946 to 1975 (d) Annual temperature trends, 1976 to 2000 on land − 1 − 0.8 − 0.6 − 0.4 − 0.2 0 0.2 0.4 0.6 0.8 1 Trend ( ° C/decade) Figure 2.9: (a) to (d) Annual surface temperature trends for the periods 1901 to 2000, 1910 to 1945, 1946 to 1975, and 1976 to 2000, respectively ( ° C/decade), calculated from combined land-surface air and sea surface temperatures adapted from Jones et al . (2001). The red, blue and green circles indicate areas with positive trends, negative trends and little or no trend respectively. The size of each circle reflects the size of the trend that it represents. Trends were calculated from annually averaged gridded anomalies with the requirement that annual anomalies include a minimum of 10 months of data. For the period 1901 to 2000, trends were calculated only for those grid boxes containing annual anomalies in at least 66 of the 100 years. The minimum number of years required for the shorter time periods (1910 to 1945, 1946 to 1975, and 1976 to 2000)
difference sea-land 0.8 0.4 CRU LSAT minus UKMO SST 0.6 0.2 0.0 0.4 relative to 1961 to 1990 Land Global anomaly ( ° C) − 0.2 0.2 − 0.4 1860 1880 1900 1920 1940 1960 1980 2000 0.0 Night Sea − 0.2 Average Sea − 0.4 UKMO SST (adapted from Jones et al. , 2001) UKMO NMAT (adapted from Parker et al. , 1995) CRU LSAT (Jones et al. , 2001) − 0.6 1860 1880 1900 1920 1940 1960 1980 2000 Year Figure 2.6: Smoothed annual anomalies of global average sea surface temperature ( ° C) 1861 to 2000, relative to 1961 to 1990 (blue curve), night marine air temperature (green curve), and land-surface air temperature (red curve). The data are from UK Met Office and CRU analyses (adapted from Jones et al ., 2001, and Parker et al ., 1995). The smoothed curves were created using a 21-point binomial filter giving near-decadal averages. Also shown (inset) are the smoothed differences between the land-surface air and sea surface temperature anomalies. Average temperature in Tallahassee November 1895 - 2004 Increase in mean Probability of occurrence (a) Consequences Possible More hot Previous weather climate temperature scenarios More Less record hot cold weather New weather climate Cold Average Hot Increase in temperature Increase in variance sea surface temperature Probability of occurrence (b) Previous climate More on land more hot cold More weather weather record More New cold record hot Increase in sea water level climate weather weather Cold Average Hot Increase in mean and variance Probability of occurrence (c) Much more Previous hot climate weather More record hot Less weather change for cold New weather climate Cold Average Hot
Toboggan glacier 1909 Water level increases about 2.8 mm per year Warming water expands: 0.5 mm Fresh water influx: melting glaciers 2004 Trivia 1990s the hottest decade, 1998 and 2005 are hottest year on record (since 1861) 2002 ,2003, and 2004 are on rank 3, 4, and 5 10% loss of snow cover since 1960s. Sea level up by 10-20 cm during the 1900s. El Niño more frequent, persistent, and intense since 1970s (relative to past 100 years). McCarthy glacier: 1909 and 2004 Consequences Increase in temperature sea surface temperature on land Increase in sea water level Increase in El Nino frequency Decrease in snow cover Changes in food production (change in world climate)
Predictions more storms more hot summers higher sea levels more rain in some areas, but drier in others sea level change will be a real threat for many town on the gulf Well, .... we are in for the ride “Our ability to quantify the human influence on global climate is currently limited because the expected signal is still emerging from the noise of natural variability…” – 1995 IPCC (2001 EPA web site) “In the light of new evidence . . . most of the observed warming over the last 50 years is likely to have been due to the increase in greenhouse gas concentrations.” – 2001 IPCC Effect on biota 86F --> all females 93F --> all males Janzen, F. J. 1994. Climate change and temperature-dependent sex determination in reptiles. Proceedings of the National Academy of Science of the United States of America 91:7487–7490.
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