Walter Jeffries wrote:I've seen several scientific articles that point to a totally non-human cause of the desertification. They time it with the up thrust of mountain ranges which changed wind patterns which in turn changed rainfall patters as well as the change in tilt of the earth which also changed weather patterns and rainfall patterns. The earth does wobble and the timing of the changes in the Sahara fit this perfectly. The mountains do up thrust and they do change wind patterns. Man has nothing to do with either of these things. There is a politically correct tendency to blame humanity for everything. This misses the real point of fixing what we can fix and do effect. Earth Day is a scam that makes people feel good by turning their lights out for an hour when they should be making a difference all year. Don't get sucked in by this sort of thing.
The factors you discuss happened in pre settlement times, we have not had an upthrust in most of the world in a very long time, and even then they are not large areas. There is plenty of radiation data that shows that there have not been significant increases over time in the suns radiation to the earth. What man does is create cumulative effects that act in concert with naturally caused effects. Add vegetation manipulation to changes in earth /mountain range formation and you have a loss of vegetation and desertification. Species evolved with changes in climate due to a variety of factors, but they did not evolve with man made disturbances outside of the range of natural variability (pre agriculture and industrialism). I can show you plenty of places that are on their way to becoming deserts, not due to any mountain upthrust or earth tilt, but due to over grazing. Now combine grazing effects with climate change and we can create alot of desert real fast.
