Friday, August 10, 2012

New paper finds increased CO2 and global warming will increase grain production


Probabilistic change of wheat productivity and water use in China for global mean temperature changes of 1, 2, and 3°C

Yujie Liu and Fulu Tao*
Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China1
Abstract
Impacts of climate change on agriculture are a major concern worldwide. However, uncertainties of climate models and emission scenarios may hamper efforts to adapt to climate change. In this paper, a probabilistic approach is used to estimate the uncertainties and simulate impacts of global warming on wheat production and water use in the main wheat cultivation regions of China, with a global mean temperature (GMT) increase scale relative to 1961–1990 values. From output of 20 climate scenarios of the Intergovernmental Panel on Climate Change Data Distribution Centre, median values of projected changes in monthly mean climate variables for representative stations are adapted. These are used to drive the CERES (Crop Environment Resource Synthesis) - Wheat model to simulate wheat production and water use under baseline and global warming scenarios, with and without consideration of CO2 fertilization effects. Results show that because of temperature increase, projected wheat growing periods for GMT changes of 1, 2 and 3°C would shorten with an averaged median values 3.94%, 6.90%, and 9.67%, respectively. There is a high probability of decreasing (increasing) changes in yield and water use efficiency under higher temperature scenarios without (with) consideration of COfertilization effects. Elevated CO2 concentration generally compensates for the negative effects of warming temperatures on production. Moreover, positive effects of elevated CO2 concentration on grain yield increase with warming temperatures. The findings could be critical for climate change-driven agricultural production that ensures global food security.

3 comments:

  1. It is only logical that an increased amount of CO2 in air will increase plant growth, including food plants. This is common practice in some greenhouses. I expect that injecting CO2 into the soil, like is being done with NH3 (ammonia) would also increase plant growth.
    All the government grants have bee directed toward finding something wrong with CO2.

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  2. The remarcable new thing in this paper is that it purposefully points to a "Climate-Change-driven" agricultural policy that uses the higher levels of CO2 as a stimulus for higher production. This sounds like the utter destruction of European, American and Australian so-called Climate policy!
    @Anonymous:
    There is no useful injecting of CO2 into the ground in greenhouses, since plants need CO2 on their leaves, not on their roots. Plants need oxygen on their roots, not CO2.

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  3. http://www.co2science.org/articles/V16/N36/B1.php

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