Climate is simply defined as the usual weather of a place. It can be different in different seasons. In the summer it can be hot and dry, while in the winter it can be cold and wet. The climate of a place can be warm all of the time or even cold enough to snow all of the time.
The Earths climte is what you get when all of the climates of the world combine. Climate change, put simply, is a change in the Earth's climate. This is usually seen as a change in the Earth's temperature or a change in where rain or snow fall on Earth.
The first thing to understand is greenhouse gases and the greenhouse effect:
-The earth’s atmosphere naturally has gases in it that we call greenhouse gases (CO2, H2O vapor, Methane, nitrous oxide, fluorinated gases, CFCs)
- These gases absorb infrared energy that is reradiated from the earth keeping it at a livable temperature. We call this the the greenhouse effect.
The greenhouse effect is a good thing - without it earth would not be habitable. All water would be frozen -life would not be sustained.
The second concept to understand is the carbon cycle:
- All life on earth is carbon based on a molecular level.
- Hundreds of millions of years ago plants and aquatic organisms died (containing a lot of carbon with them) they did not decompose, but rather as conditions around then changed, they chemically changed keeping the energy that was within them and the carbon trapped. These are fossil fuels - coal, natural gas and petroleum.
- The earth has a natural balance for carbon - there are fast and slow parts. Carbon sinks like the atmosphere, ocean and rocks store carbon for hundreds of thousands - thousands of years before being released in different ways. Living things rapidly exchange carbon.
During the industrial revolution, humans discovered fossil fuels as an energy source. We release the energy that was trapped inside the once living organisms by burning them.
Burning them also releases the carbon inside as carbon dioxide, a greenhouse gas.
The Industrial revolution was the start of human-caused climate change.
Evidence in ice cores, rocks, and fossils have shown that the current amount of CO2 in our atmosphere has surpassed any natural fluctuation that happened within the past 800,000 years.
The climate has changed in the past going through natural cooling and warming periods from other natural factors, but never before do we have evidence that it has happened so rapidly.
As the populations has continued to grow, our reliance on energy grows with it. (200 years ago there were less than 1 billion people on earth, and between 1900-2000 the population grew from 1.5 to 6.1 billion. Today there are 7.6 billion people on earth) those are crazy numbers when you think about it - there is my one subjective slip.
Carbon dioxide (CO2) is often what you hear most about because of human emissions, but it is not the only greenhouse gas that is of concern. Agriculture and fossil fuels emit a lot of methane, which has a shorter lifespan than CO2, but traps 25x more heat.
All of this means nothing if its not backed up by science. Below are sources and outlets of information that build the science behind all of those concepts, but this is here to wrap it up in a nutshell for you! Hope it helps.
Information to build the science behind all of those concepts mentioned throughought the site: