18th Century Anthropogenic Climate Change

More evidence of human impact on climate with not a CO2 molecule to be seen. In this case the effect of cultivation on the monsoon in Asia during the 18th and 19th centuries when the Indians and Chinese were busy doing what the Indonesians are today - burning down their rain forests for cultivation and causing reduced precipitation - and an increased risk said cultivation would fail - as a result. Oh well, we humans never learn by past mistakes do we .....

There's a good summarisation on Science News: Cultivation changed monsoon in Asia whilst the full paper can be accessed here - us mortals have to settle for just the abstract I'm afraid but Roger Pielke Sr does quote the following extract from the paper on his excellent website:

“Changing the land cover/use from forest to croplands can affect the global and regional climate through changes in the energy and water balance at the earth’s surface…. Among the various effects of vegetation change, 2 factors have been shown to have a major influence on the energy and water balance: (i) an increase in surface albedo leading to a reduction in solar energy absorption at the surface and (ii) a decrease in surface roughness, resulting in low-level wind speed intensification. As a consequence, the partitioning of turbulent heat fluxes into its sensible and latent heat fluxes would subsequently affect the planetary boundary layer and deep cumulus convection and, hence, the large-scale atmospheric phenomena…”