The Chemistry of Climate Change

Increase in CO2

Atmospheric CO2 levels have increased 26% since the industrial revolution

Total Dry Mass of Atmosphere: 5.13x1018 kg

Average molar mass of the atmosphere: 29 g/mol

or 1.8x1020 moles

Mass of Carbon from fossil fuel combustion per year: 6x1012 kg or 5x1014 moles

increase of 5x1014/1.8x1020=2.8 ppmv

Hypotheses:

1. Global Warming is not Occuring

2. Global Warming is Occuring but due to natural cycles

3. Global Warming is Occuring and due in part to human activity

Questions regarding data sets:

1. What are the maximum and minimum values presented?

2. How was the data collected?

3. Where was the data collected?

4. How should the data be interpreted?

5. What data appear to be the most significant indicators or Global Warming? Which data appear to be less relevant?

Global Warming?: Houston

Houston Summer Months and Number of Days at a Temperature >96o

Year June July August September Total 1948 3 14 18 2 37 1954 2 15 14 2 33 1962 0 11 19 1 31 1963 5 8 11 6 30 1969 9 20 9 0 38 1978 1 18 13 0 32 1980 19 25 24 10 78 1982 5 24 14 3 46 1985 3 3 14 5 34 1986 2 20 10 0 32 1988 5 15 16 4 40 1990 14 4 23 4 45 1993 1 16 26 6 49 1994 6 19 4 2 31 1995 7 14 11 11 43 1998 15 30 20 4 69 1999 0 5 29 8 42 2000 0 22 24 7 53 2001 0 7 16 0 23 2002 2 12 5 0 19 2003 4 2 8 0 14 2004 1 8 8 2 19 2005 7 8 7 7 29

Year Annual Rainfall (Inches)

1900 72.86

1919 72.38

1949 71.19

1973 70.16

1979 83.02

1981 82.14

1997 78.41

2001 71.18

Annual Rainfall* in Houston, TX

*for years when the annual rainfall exceeded 70 inches

Global Warming?: Greenhouse Gases

Preindustrial 1960 1980 1990

CO2(ppmv) 295 315 325 352CH4(ppbv) 975 1270 1570 1675N2O(ppbv) 290 300 303 310CFC-11(pptv) 0 11 173 275 CFC-12(pptv) 0 33 297 468CFC-113(pptv) 0 0.2 15 51CFC-114(pptv) 0 0.2 4 7CFC-115(pptv) 0 0 2 5CCl4(pptv) 0 75 95 105CH3Cl(pptv) 600 600 600 600

Evolution of Trace Gas Mixing Ratios

Global CH4 Levels

Global N2O Levels

Global Temperature

The effect of mean and variance increases on temperature

Global Warming?: Severe Weather

Major Storms in the United States

Tornadoes in the United States