To prevent the tipping point after which catastrophic environmental change will happen, what needs to be done?

A) Carbon dioxide emissions must be eliminated in the next two years.
B) Global greenhouse gas levels must peak no higher than 450 ppm and start declining by 2015.
C) All greenhouse gases need to immediately be reduced below their levels in 1990.
D) Carbon dioxide emissions must not rise more than 800 ppm, double the levels in the atmosphere today.


B

Environmental & Atmospheric Sciences

You might also like to view...

________ are the most common materials precipitated as cement, which binds loose particles of sand into a solid sedimentary rock.

A. Feldspar and calcite B. Calcite and silica C. Clay and silica D. Silica and hematite E. Calcite and fluorite

Environmental & Atmospheric Sciences

The Colorado River is an example of a large wash

Indicate whether the statement is true or false

Environmental & Atmospheric Sciences

If a measured distance of 10 inches on a map represents an actual distance of 5 miles, what is the fractional scale of the map?

What will be an ideal response?

Environmental & Atmospheric Sciences

According to the Meteorological Service of Canada, which of the following defines a severe thunderstorm?

A. a storm having a tornado B. a storm having surface wind gusts below 90 km/h C. a storm having hail less than 2 cm in diameter D. a storm having misty rain

Environmental & Atmospheric Sciences