It can certainly be argued that these effects are also being observed in our climate. Some of these effects can also be attributed to pollution and habitat destruction not directly related to global warming.
Harder to predict, perhaps less likely effects of our predicted temperature increase over the next century are changes in ocean circulation patterns and ice sheet surges. These effects would cause a drastic disruption of our climate.
We need to remember that the rate of temperature change is an order of magnitude ten to twenty times greater than that of the natural fluctuations of the past. Also, keep in mind that the difference between an ice age and an inter-glacial period is between five and six degrees Celsius. A rapid two-degree change could have significant effects on our global climate.
Our Picture?
Modeling the climate and predicting likely outcomes based on the buildup of greenhouse gasses is complex and controversial.
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