Definition:An increase in Earth's mean global temperature.

Problem:Hotter… and hotter… and even hotter.How will life on Earth survive extreme temperatures?

Basically the problem is that humans are releasing TONS of CO2 into the atmosphere. Excess CO2 prevents heat from escaping, instead trapping it in and raising the temperature of Earth.

Ideally humans exhale CO2 which plants need. Plants give off oxygen as a waste product of photosynthesis, and humans inhale that oxygen. This cycle helps keep the CO2 concentration in the atmosphere fairly steady.

However, humans engage in activities that let off much more CO2 than plants could ever use up. This excess CO2 is added to the atmosphere.

The three most abundant sources of this excess of CO2 are the burning of fossil fuels, cement making, and deforestation.

•Yellow lines – heat from sun•Blue lines – heat leaves to outer space•Orange lines – heat returned to Earth b/c of atmosphere•Sun’s rays blocked = freezing•Atmosphere keeps in too much heat = heated

*Ray 1 – absorbed by air*Ray 2 – absorbed by ground to some to space*Ray 3 – reflects from ground to space*Ray 4 – reflects to space by atmosphere

Is the globe really warming? Many scientists believe global warming doesn’t exist and that people are worrying for no reason. GW supporters said that 2007 would be one of the hottest years on Earth. It was actually one of the coldest years. Many places that hadn’t received snow in almost a century gathered snowflakes on their streets.

*Glaciers are shrinking!... But some are getting bigger. GW attackers say we don’t know enough about icebergs to explain this, so we shouldn’t link it to global warming.

*The Earth’s temperature is getting warmer!...wrong again, it’s getting colder.

*Politics have skewed information.

*Earth’s climate was even hotter than it is now centuries ago – we aren’t looking at the “big picture.”