1. What does under sampling of climate records mean? Describe some of its effects.

Under sampling of the climate records is where there is not enough data collected and the data that is collected is not to try and balance out the data sets. This technique is used by scientists and this type of sampling can have an impact by losing some important information. This technique will still be used even with disadvantages because it is one way we can try and get a better idea of all the data collected and kind of put together a picture or an idea of what we think might have happened or help support or take away from theories or ideas. 

2. What evidence exist that prove that the present day Sahara Desert was one a lush tropical forest environment?

Some of the evidence that exists that the Sahara Desert was once a lush tropical forest environment is that we can use computer models to show that the Sahara Desert was once a tropical forest. The earth tilt have changed and the change of tilt and after the ice age there were tried and increased rain as well as lakes in the Sahara. Something else that I could think about would have been the specific heat of the land would be less compared to the water which would pull in moist air from the ocean and bring in precipitation.