People blame cars and factories for the pollution and h igher temperatures. Actually, the gases that these produce already occur in the atmosphere and are essential to keeping our Earth warm. There are a wid e range of natural systems that are being researched as potential causes of global warming. There have also been natural occurrences that may have caused the earth to warm recently. The changes in global temperature have been researched in many different ways including tree rings and the contents of air bubbles trapped in soil or ice cores.
Scientists studying tree rings look for wide rings, signifying a warmer year.
Borehole records of ice and soil core differ slightly in results. The research that has been done in global warming is very confusing and contradictory. Although most studies conclude that global warming is happening, there is no accurate way of knowing what is in store for our future. If the cause of global warm ing is from humans, changes in our daily lives need to be taken. This would be benefici al to our atmosphere, but it would also cut down on our use of non-renewable resources.