Climate Dynamics 11:670:461 Alan Robock robock@envsci.rutgers.edu Lecture 2, 9/8/14 Climate Dynamics 11:670:461 Alan Robock Department of Environmental Sciences Rutgers University, New Brunswick, New Jersey USA robock@envsci.rutgers.edu http://envsci.rutgers.edu/~robock

But, what is a “greenhouse gas” anyway? Nitrogen (N2), oxygen (O2), and argon (Ar) make up for 99% of the atmosphere, but are not greenhouse gases. Water vapor (H2O), carbon dioxide (CO2), methane (CH4), ozone (O3), and nitrous oxide (N2O) are greenhouse gases. A greenhouse gas absorbs infrared radiation, which creates molecular vibration and bending. Collisions transfer energy to heat the surrounding gas. Water vapor (H2O) vibration modes http://www.lsbu.ac.uk/water/vibrat.html

Produced by Gary Strand, NCAR CCSM Climate “Forecasts” Produced by Gary Strand, NCAR (°C) (°C)

IPCC AR4, Chapter 1 Fig. 1.1

Bretherton Diagram Fig. 1.2

Bretherton Diagram Fig. 1.2

Tropospheric aerosols mask warming (global dimming) Greenhouse gases dominate Recovery from volcanic eruptions dominates http://data.giss.nasa.gov/gistemp/graphs_v3/Fig.A2.pdf

Desire for improved well-being Consumption of goods and services Impacts on humans and ecosystems SUFFERING CONSERVATION Consumption of energy EFFICIENCY ADAPTATION Climate change SOLAR RADIATION MANAGEMENT CARBON DIOXIDE REMOVAL LOW-CARBON ENERGY CO2 emissions CO2 in the atmosphere After Ken Caldeira

Annual average surface air pressure. Interval 50 mb. Fig. 2.1

Annual average surface air pressure. Interval 50 mb. Fig. 2.1

Fig. 2.2

Annual mean 900 mb geopotential height (m) Fig. 2.3

Annual mean 900 mb geopotential height (m) Fig. 2.3

Seasonal 900 mb geopotential height (m) Fig. 2.4