BLS 358 Global Environmental Issues PS#1

 1) The global CO2 emissions from fossil fuel burning are around 5.4 x 109 metric tons. On a per capita basis Americans emit ~5.2 metric tons per person. By contrast, China, with 1 billion people, has per capita emissions which are about 1/10 of these. Calculate what China’s total emissions WOULD BE if they were to reach the same per capita emissions as the U.S.

 China’s total emissions would be _________________ metric tons.

 By what percent would the global fossil fuel CO2 emissions increase if China were to achieve this level?

 The increase in the global fossil fuel CO2 emissions would be _______________%.

 2) Consider the following data:





Current population (millions)




Current growth rate (%)




Approximate doubling time (years)

Population in 30 years

 Complete the table assuming a constant growth rate for the next 30 years. (Hint: if you are unsure about the doubling time see your text, Ch. 6).



 3) In the upper atmosphere (stratosphere) ozone is continuously being destroyed and regenerated in a natural cycle:

Oxygen Û Ozone 

There is about 3.0 x 1015 grams of ozone present and about 1.1 x 1017 grams/year are produced. Assuming that this cycle is in balance, what is the average lifetime (in days) for a molecule of ozone in the stratosphere?





4) Consider the global cycle for element X below:

Atmosphere (20)

÷ õ

Land (50,000) ð Ocean (500)

The values in parentheses give the total burden of element X in that reservoir (in teragrams, 1012 grams). Assume that system is in balance and that the fluxes:

Ocean Þ Atmosphere; AtmosphereÞ Land; and LandÞ Ocean are all equal to 10 teragrams per year. Calculate the average residence time (in years) for element X in each reservoir.

Residence time for element X:

Land _____________ years

Ocean _____________ years

Atmosphere _____________ years


5) Choose any two countries from Problem 2 and compare some of the demographic data to explain the population growth. For example you might choose to focus on the distribution of age groups in that country, average number of children per family, or some other indicators of population growth. A good place to get data is at the US census web site:

This is meant to be a short exercise. Your answer should not to exceed one paragraph.