2.  Large masses of ice that form on land  for a number of years, more snow falls in winter than melts in summer  deform and flow due to their own weight  force of gravity  strength of ice

5.  Stationary Glacier  Accumulation = Ablation  Receding Glacier  Accumulation < Ablation  Advancing Glacier  Accumulation > Ablation  How can you tell?

7.  End (terminal) moraine  Kettle lakes

8.  Light is one STRANGE phenomenon!  Electric and magnetic forces are really two aspects of the same phenomenon, which we now call electromagnetism  Light exhibits BOTH wave-like (wavelength) AND particle-like (photon) natures

10.  Hot objects emit more radiation per unit surface area than cold objects

11.  Hot objects emit shorter wavelength (higher energy) photons than cold objects

12.  Pressure: a measure of the weight of overlying molecules of air  PSI  mmHg or inHg  Bar  Gravity pulls the molecules toward Earth

14.  Can I ask a simple question?  If Hot Air rises, why is there snow in the mountains?  Answer is not so simple!  How is each layer heated? It needs:  Heat Source, which emits some…  Type of Radiation  Substance that absorbs a particular set of photons.  Good Absorbers make Good Emitters – BUT  Not all materials are GOOD absorbers – some are SELECTIVE absorbers!

16.  Temperature rises with increasing altitude  Energetic rays of the Sun are absorbed by ions of O and N  Highest temperature of any layer is reached - more than 1000°C!!  Pressure is VERY low - very few atoms or molecules around  Thermosphere grades out into the vacuum of space.

17.  Temperature drops with increasing altitude  “Heat source” is hot material (atoms) escaping from the Stratosphere  Ozone doesn’t exist in this thin air  Sun’s rays are extremely energetic, but there is nothing there to absorb the energy!  Top of Mesosphere is the Mesopause.

18.  Temperature rises with increasing altitude  The SUN must be the heat source!  OZONE absorbs UV rays and becomes warmer  “Heat Rises”, but... ...what this really means is that “Air that is warmer than its surroundings will rise”  Air doesn’t rise much in Stratosphere - lack of vertical motion results in layering  Top of Stratosphere is called the Stratopause.

19.  This is also known as the “Weather Sphere”  Temperature drops with increasing altitude  Rate of decrease with altitude is known as the Environmental Lapse Rate (ELR)  Average (or Normal) ELR is around 6.5°C/km (3.5°F/1000 ft), but varies widely with place, season, etc.  Earth is the source of heat for the Troposphere  Discussed further in a moment  Top is defined where the temperature stops dropping - called the Tropopause.

20.  Temperature DROPS with altitude  Abundance of Greenhouse Gases  Could this be heated by the Sun?  Gamma, X-rays absorbed in Thermosphere  UV absorbed in Stratosphere  VIS passes through it all!  How do we know that?

22.  Reflectivity of surface  Fresh snow:  Asphalt:  Green Forest:

23.  H 2 O  absorbs ~ 5X more microwaves than all other GHGs combined!!  Can we control its abundance in the atmosphere?  CO 2 – stable in our atmosphere  Now at about 400 ppm (0.040%)  Can we control its abundance in the atmosphere?  CH 4 (Methane)  Very strong absorber at  Breaks down to H 2 O and CO 2

26.  Think of GHGs as baseball mitts…  Are mitts being added?

27.  Increase in CO 2  Increase the Temperature  Increase the Temperature  Increase the H 2 O  Increase the H 2 O  Increase the Temperature  Repeat…

28.  Popclock: http://opr.princeton.edu/popclock/ http://opr.princeton.edu/popclock/

30.  Globally, average surface temperatures will increase  Globally, average precipitation will increase, but its distribution is uncertain  Northern hemisphere ice will decrease, southern hemisphere ice may increase  Arctic land areas will experience wintertime warming  Sea level will rise at an increasing rate with drowning of low- level coastal plains  Decreasing soil moisture in the northern hemisphere may make farming nearly impossible in much of North America and Europe  Plants and animal ranges will expand in some cases, shrink or disappear altogether in others