Differences Due to Vegetation Change

Only a few of the new generation of computationally expensive dynamic vegetation models can accurately simulate a situation 

In temperate regions of the Northern Hemisphere, widespread maize production may cause an increase in the isotopic content of the regional carbon. stock (i.e., a. shift to heavier C signatures). However, this signal would result in a higher global mean c5 Cer and a lower Ag thus it cannot explain the observed 5%o difference in A. at midlatitudes between field observations and B10ME3.5 estimates. 

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