Final Climates Quiz

• This is certainly the topic of the day considering the controversy surrounding anthropogenic release of CO2 which in effect changes the composition of the atmosphere. Thus, this forcing can be considered "external." However, if humans are part of the earth-atmosphere system, couldn't we argue internal?
• Two possible ways for


  1. Time scales shorter than a climatic averaging period, e.g., hours to several days (synoptic period)

  2. Time Scales of longer than a climatic averaging period, E.g hundreds to millions of years
• Even a most cursory or rudimentary examination of the geologic record suggests that climate change actually occurs
• Examples of climate change


  • Medieval warm (800-1350 anno domini)
  • Climatic optimum 5-8 KYA
  • 2 MYA Pleistocene ice ages (at least 6, see articles in "Science") and interglacials
  • Cretacious warmth (68-130 MYA)
  • The cool, glaciated permo-carboniferous (~300 MYA)
• The popular perception field by global warming proponents is that climate change is global. It could be given teleconnectivity. Even some atmospheric scientists tend to think in global terms. If one looks at climate in more detail, one tends to find that the differences are primarily regional
• The pleistocene ice ages affected mostly mid and high latitude NG, with equatorial region and SH unaffected relative. Global temperatures dropped about 2 C (see how sensitive climate can be? How close we are to ice age?). But this did not occur equally everywhere
• Milutin Milankovic


  Serbian mathematician famous for postulating the theory of long term climate change as related to Earth's orbit
• Variations in Earth's orbit


  • Variations in eccentricity (~100 KY)
  • Variations in obliquity (~40 KY)
  • Precession of the equinox (~26 KY)
• Weather/General Circulation Model


  A hypothesis, in the form of mathematical statements, that describes a process or processes that are physically important in describing the climate and/ or climate change. The physical consistency of the model formulation and the agreement with observations serve as a test of the hypothesis
• The Scientific method


  1. Collect data

  2. Investigate the issue

  3. Identify the problem

  4. Form hypothesis

  5. Test hypothesis

  6. Accept or reject hypothesis based on conclusions
• Two distinct types of climate models


  • Diagnostic or equilibrium model (equilibrium climate model – ECM) with time derivatives either implicitly or explicitly set to zero
  • Prognostic models, where time derivatives are crucial and with the variation with time and particular variables the desired result (I.e., a time series)
• Inductive reasoning


  When we say X is important, Y is important, and Z, w, and v are smail thus x=y. This is scale analysis and we can apply typically to equations or models with a priori reasoning
• Deductive reasoning


  Fundamental principles are used to derive conclusions
• The effective temperature of the earth-atmosphere system is reasonably close to the triple point of water, thus in essence incorporating is a very important and powerful influence on our climate
• Global Warming/Climate Change: Yes, climate is warming. Humans are contributing, but to what degree. There are many things about the climate system still not understood. What should we do about it?