Assignment 3

1. a) In 2012 your favorite climate denier friend makes the following argument to you:
   
   
   • In 1952 the average temperature of the United States was 52.33
   • In 1973 the average temperature of the United States was 52.31
   • In 2008 the average temperature of the United States was 52.31
   
   
   And uses that data to claim that there can be no warming going on.
   
   What is your response to this argument?
   
   b) Now let's use all the data
   
   The following table shows US average annual temperatures in three separate time periods 1950-1962, 1970-1982, 2000-2012. Using the Z-test determine if there is a significant difference in mean values between the 2000-2012 data set and the other two data sets.
   
   c) From this analysis, give an argument either for or against that the annual temperature of the US is increasing as a response to global climate change
   
   

   1950,51.43 1951,51.15 1952,52.33 1953,53.39 1954,53.34 1955,51.72 1956,52.35 1957,52.10 1958,51.97 1959,52.13 1960,51.45 1961,51.88 1962,51.90

   1970,51.64 1971,51.71 1972,51.39 1973,52.31 1974,52.30 1975,51.53 1976,51.51 1977,52.58 1978,51.07 1979,50.92 1980,52.41 1981,53.15 1982,51.37

   2000,53.27 2001,53.67 2002,53.21 2003,53.30 2004,53.12 2005,53.64 2006,54.32 2007,53.67 2008,52.31 2009,52.39 2010,53.02 2011,53.21 2012,55.34

   
   
   
2. There are currently (as of  July 2018)  411 parts per million of CO₂ in our atmosphere. In July 2000 the concentration of CO₂ was 365 ppm.

   a) calculate the average exponential growth rate in this period

   b) at this growth rate what will the concentration of CO₂ in the year 2100.

   A reasonable approximation of the amount of surface temperature (in degrees C) increase as related to CO₂concentration is given by:

    

   ΔT = 0.8 * ΔF

   where for CO₂

   ΔF = 5.35 * LN(C_now/C_before);   C_before = 280 ppm

   Note that LN stands for the natural logarithm;  for instance ln(10) = 2.32 (just type ln 10 in to Google) 

   ΔF (what we call climate forcing) represents the change in flux due to changing CO2 levels and that determines ΔT

    

   c) Using the result obtained in Part b, what is the predicted temperature change in the year 2100 and is this prediction above or still below the Paris accord agreement of no more than 2C before 2100 above the pre-industrialized temperature?

    

   Over the last few years, CO2 growth is occurring at a larger rate than long term average. The following list gives you the necessary values to compute the relevant growth rates for the question below.
   
   

   Jan 1970  325 ppm
   Jan 1990  353 ppm
   Jan 2005  378 ppm
   Jan 2019  411 ppm
   

   
   
   d) Using the same calibration as above, calculate the exponential growth rate and predicted 2100 temperature from that growth rate for the periods
   • 1970-1990
   • 1990-2005
   • 2005-2019
   
   
   e) Now suggest why climate policy should be based on the most recent data and not the longer term data.
   
   
   
   
3. Do some research and summarize the reasons that some scientists think there is a likely chance that "Runaway Methane Global Warming" will actually happen. Also summarize some of the past geological evidence for past runaway events (e.g. methane burps). Finally, conclude whether or not, based on your research, you think this is a serious concern.

   
   
   
   
   

4. Do some research on Arctic Sea Ice extent and a) argue whether or not the current melt rate of the Arctic Sea Ice is a significant problem or is it, in fact, a blessing because it will positively affect world trade.
   
   b) Based on your research in what future year is the Arctic Ocean likely to be ice free?
   
   
   
   
5. Do some research on the recent policies that have been put in place by the European Union regarding climate change and summarize them. Also state some reasons why such policies are unlikely to be adopted by the United States.