Global Climate Change
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Transcript of Global Climate Change
Global Climate Change
Ashok KumarAbhishek Bhat
University of ToledoSept. 21, 2009
Defined as the weather conditions averaged over some period of time, the seasonal distribution, and the extremes in weather for a place.
Climate: Normals, means, and extremes of different weather elements.
Extremes: coldest, warmest, driest, wettest, snowiest, or cloudiest month or year.
What is Climate?
Climatic controls include latitude, elevation, topography, presence of water bodies, and atmospheric circulation.
Climate norms are computed over a 30-year period since 1933. They are adjusted after every decade.
Air mass climatology is also used to describe climate.
Climate Controls
By altering the radiational properties of the earth’s surface (e.g.: albedo)
By releasing waste heat into the atmosphere
By changing the concentrations of certain key gaseous or aerosol components of the atmosphere
Influence of Human Activities
Measures of Climate Change
Greenhouse Effect and Greenhouse Gases
Global Climate Change Models
Global Climate Change
Average Temperature
Precipitation
Wind
Glaciations
Frequency of Extreme Events
Measures of Climate Change
Determination of Past Global Temperatures
◦ Historical documentation◦ Tree rings◦ Changes in ice volume◦ Changes in sea volume◦ Fossil pollen analysis◦ Geologic observation related to glacial movement
Temperature
Average Temperature Trend
Palmer Drought Severity Index (PDSI)
Index Severity-2 Moderate Drought-3 Sever Drought-4 Extreme Drought2 Moderate Rainfall3 Sever Rainfall
Changes in Ice Volume
Climate Change and Weather
Greenhouse Effect
Greenhouse Gases The greenhouse
effect◦ Continuous warming◦ O.5 – 0.7 0c warming
Greenhouse gases◦ Carbon Dioxide◦ Methane◦ Nitrous Oxide◦ CFC◦ Water Vapor
Sources and Estimated Lifetime for Selected Pollutants
Half Life of Contaminants
Contaminants Approximate Residence Time
CO2 15 yr
CH4 10 yr
N2O 150 yr
CO 65 daysCFC 11 65 yr
Changes in Greenhouse Gases and corresponding change in
Temperature
Carbon Cycle
Carbon Dioxide
CO2 Emissions Global CO2 Emissions
Methane
Global Methane Emissions Methane Measures
N2O
N2O Concentration N2O sources
Ozone Depletion
Ozone Depletion
CFC Sources
CFC Source Distribution CFC Source Distribution
CFC Concentration
CFC-11 Concentration CFC-12 Concentration
Water Vapor
General Circulation Models (GCMs) are a class of computer-driven models for weather forecasting, understanding climate and projecting climate change, where they are commonly called Global Climate Models.
Different Types of Models◦ Simple General Circulation Model (SGCM)◦ Atmospheric GCM◦ Oceanic GCM◦ Coupled Atmospheric-Oceanic GCM
Global Climate Models
Global Atmospheric Model
GCM
Model Projections Model Accuracy
CO2 Emission Calculation:CO2 = (Pi)*(Foi)*Ci
P: Amount of fuel FO : Fraction oxidized C : Average carbon content i: Particular fuel type
Change in radiative forcing:For CO2
ΔFCO2 = K3 ln [(co2)/(co2)0] K3 : 6.3 (W/m2)
Climate Change Calculations
Surface temperature change:ΔTs = ΔF * λ
ΔTs: Surface temperature ΔF: Radiative forcing λ: Climate sensitivity factor (0.57 in 0C/W/m2)
Cont…
GCM Performance
Model Performance Global Warming Projection
IPCC, 2007: Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change [Solomon, S., D. Qin, M. Manning, Z. Chen, M. Marquis, K.B. Averyt, M. Tignor and H.L. Miller (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, 996 pp.
IPCC, 2007: Climate Change 2007: Impacts, Adaptation and Vulnerability. Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, M.L. Parry, O.F. Canziani, J.P. Palutikof, P.J. van der Linden and C.E. Hanson, Eds., Cambridge University Press, Cambridge, UK, 976pp.
IPCC, 2007: Climate Change 2007: Mitigation. Contribution of Working Group III to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change [B. Metz, O.R. Davidson, P.R. Bosch, R. Dave, L.A. Meyer (eds)], Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA., XXX pp.
IPCC, 2007: Climate Change 2007: Synthesis Report. Contribution of Working Groups I, II and III to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change [Core Writing Team, Pachauri, R.K and Reisinger, A.(eds.)]. IPCC, Geneva, Switzerland, 104 pp.
Climate Change, Retrieved November 24th, 2008. Web site: http://www.wikipedia.com Global Warming , Retrieved November 24th, 2008. Web site:
http://www.wikipedia.com Greenhouse Effect , Retrieved November 24th, 2008. Web site:
http://www.wikipedia.com Atmospheric Cleansing and Current Air Pollution Issues, Retrieved November 24th,
2008. Web site: http://www.eng.utoledo.edu/~akumar/IAP1/mainpage.htm
References
Questions?