Water

What percent of water is used for agriculture?
67%
What percent of water is freshwater? And what percent of Earth’s water is available for drinking?
2.5%, 0.01%
How much of the water cycle are we using?
10% (4,000 km^3/r)
How much was the Aral Sea reduced by?
80% in 50 years
How much has the Ogallala Aquifer’s surface dropped?
10% since 1950
What is salt water incursion?
It is the seepage of salt water into fresh water aquifers when the aquifers are pumped to quickly.
What is the global energy consumption?
15TW = 473 EJ
What percent of the energy we use comes from fossil fuels?
85%
What is the ranking of how bad fossil fuels’ emissions are?
coal > oil > natural gas
What is decarbonization?
We are getting fewer units of energy per unit of energy consumption.
How much do we need to reduce emissions by?
3.8 Gt by 2020, 12.8 Gt by 2030
How much greater will energy demand be in 2030 than it is today?
2/3 greater
How much of the world’s energy comes from nuclear plants?
15%
What is NPP? What is the global level of terrestrial NPP?
Net primary productivity (energy fixed by plants). 60 PgC/yr
What percent of NPP do we use?
30%
What is a species area curve?
S = cA^z
S is number of species
c is the constant (dependent on species)
A is the area
z is a set value (.25-.55 for islands, .1-.2 for a single province, 1 between provinces)
What percent of species are committed to extinction?
15-37%
Describe the findings of the Millenium Ecosystem Assessment:
-Over past 50 years, ecosystems have changed more rapidly and extensively than ever before
-60% of ecosystem services evaluated are being degraded or used unsustainably