Global Climate Change: The Evidence

Presentation by: Rosa Jaime

Human activities can effect the climate change. Here are some changes that have happened in

recent times…• Raise in carbon dioxide co2

• Species extinction

• Nitrogen gasses have risen

• Massive increase in human population

Climate and What Controls It

• Sun• Tilt of the earths axis• The orbit of the earth around the sun• Changes in geography• Energy input from the sun and how it is

redistributed and outputted into space• Climate changes when input, redistribution,

or output factors change, this is called “forced behavior”

Climate

• The reasonable expectations and possibilities of temperature and seasonality is climate

• Climate change is a shift in these possibilities and expectations

Climate Models

• Mathematical summaries about the mechanisms of the climate system (they are not chances or estimates)

• They reproduce main features of modern climate

• They capture changes in ice ages (in time and geographically)

Greenhouse Effect

• Greenhouse gasses are…

• Carbon dioxide

• Methane

• Water vapor

• Nitrogen oxide

• These four gasses plus CFC’s have been directly increases by humans

Feedbacks

• Water vapor feedbacks

• Warmer atmosphere is wetter

Green house gas (+)

• Cloud Radiation

Reflect solar radiation (-)

Absorb heat (+)

Closing Facts

• Ocean warming is big evidence

• Common patterns show late 20th/early 21st centuries as the warmest

• Large, unprecedented increases in co2 and other greenhouse gasses

• Expect great climate change and global warming