The primary climate drivers are the Milankovitch cycle and Cosmic Rays.

http://en.wikipedia.org/wiki/Milankovitch_cycles

http://www.sciencebits.com/CosmicRaysClimate

This is a phenomenal book showing how real science is done. It teaches a lot about geology and orbital mechanics. One of the best books of its type I have ever read.

http://www.amazon.com/Ice-Ages-Solving-John-Imbrie/dp/0674440757

Here is a good introduction with historical perspective on temperatures. Note the heavy contributions from Geology and Physicists, as opposed to "modellers."

http://www.geocraft.com/WVFossils/ice_ages.html

So he is beginning with a premise that CO2 is bad? That warm temperatures are bad?

The great Famine was when the Medieval Warm Period ended. That period was warmer than today's era. Societies around the world collapsed - Europe, Cahokia in North America, China, etc. This then set the stage for further disasters such as war and plagues.

http://en.wikipedia.org/wiki/Great_Famine_of_1315-1317

Not much has changed ( and not more can be added ) since Arrhenius did the first calculations on the effects of CO2 on global temps. Increases in CO2 have diminishing returns past 200ppm and we are nearing the saturation point for further temperature increases.

http://en.wikipedia.org/wiki/Svante_Arrhenius

Furthermore, much of the "modelling" and the "data" it was based on done to date has been shown to be fraudulent. It has to be thrown out and we have to start over.

As a good general current reference, this blog has consistently won best science blog and there is a wealth of information in the sidebars on climate. Posts come from all the sides in the debate and the commentary is quite good.

http://wattsupwiththat.com/

It has a very good reference and resource list.

http://wattsupwiththat.com/resources/

http://wattsupwiththat.com/reference-pages/