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Landsats independently increase crop yield—predictions allow the market to adapt and farmers to harvest enough.
Doraiswamy et al 7 (Paul C., Bakhyt Akhmedov b , Larry Beard c , Alan Stern a and Richard Mueller c a USDA, b Science Systems and Associates, Inc. c USDA, http://www.ars.usda.gov/SP2UserFiles/person/ 1430/ISPRS_AGRIFISH_Final.pdf , accessed 7/8/11) CJQ
Timely and accurate prediction of crop yields is critical for agricultural markets, planning and development. Daily frequency of MODIS data acquisition at 250 m pixel resolution offers a great potential for use of the data and products in operational yield prediction programs. In this study, a simple algorithm that uses near-real time MODIS imagery and products was developed to predict crop yields at county and state levels. The algorithm includes crop-specific classification and yield prediction prior to crop harvest. The crop classification was developed using a decision tree algorithm that relied on the characteristics of crop growth phenology without the need for ground-based data. The classification accuracies were compared with the USDA NASS Landsat based classification data and found to be acceptable for yield predictions. The correlation between NDVI and crop yields and between surface temperature and crop yields are integrated in a multidimensional regression model for predicting yields at the county and state levels. Differences between the NASS state level yield estimates and the regression algorithm predictions for both Iowa and Illinois for the 2006 season was less than 4 b/ac for corn and less than 2 b/ac for soybeans. The quality of MODIS data is very critical for crop yield predictions and this paper describes some of the steps that we achieved to enhance the quality of data for cloud cover and atmospheric effects. The computational scale appeared to make a difference in the tolerance on the imagery data quality. Although the same algorithm was used for both state and county level yield predictions, the county yield predictions appeared to be more sensitive to quality of the images and the yield predictions were not as well correlated with the NASS estimated yields. Another important factor in this lower coefficient of determinations at the county level was that the NASS estimates have an error that is not reported. However, assuming an error in the NASS county yield estimates, the predictions are well within a 20% standard deviation of the estimates.
Famine – IL – China Wheat
Chinese wheat crunch coming now—drought means they'll have to import wheat; crashes economy.
Bradsher 11 (Keith, Hong Kong Bureau Chief of the NYT, http://www.nytimes.com/2011/02/14 /world/asia/14china.html?_r=1, accessed 7/8/11) CJQ
HONG KONG — It is weather with global breadbasket implications. Even as senior Chinese officials exhort local officials to do everything possible to cope with a severe drought in the country’s wheat belt, the government is trying to reassure the public that food prices will not rise. China’s drought-control headquarters posted a statement on its Web site on Sunday that described conditions as “grim” across a wide area of the wheat belt in Northern China and called for emergency irrigation efforts. Agricultural experts say it is too early to assess the damage to the wheat harvest. “We are in the winter months now, when it is typically drier anyway, so the seedlings should still be alive,” said an expert at Shandong Agricultural University who would provide only his family name, Wang. “But if the weather turns warmer and there is still no rain, then we will not be talking about lower agricultural production, but rather zero production, because the seedlings will all be dead.” The worries go beyond China, which has essentially been self-sufficient in grain for decades. The concern is that China, with 1.3 billion mouths to feed, may need to import wheat in volume, creating shortages elsewhere. Wheat prices in Chicago jumped nearly 2 percent on Tuesday when the United Nations’ food agency issued a rare alert that China’s crop was in trouble, and prices remain near their highest level since a steep spike in commodity prices in 2008. Light snow and rain fell on north-central areas of China’s wheat belt on Wednesday and Thursday, partly because meteorologists had fired artillery shells and truck and aircraft-mounted rockets loaded with the cloud-seeding chemical silver iodide. Because of the recent precipitation, drought-control officials said last week that about one-tenth of the drought-stricken area had received adequate moisture for now. Prime Minister Wen Jiabao assured the public in televised remarks late last week that the supply and demand of grain were “basically” in balance and that large stockpiles were available. The Finance Ministry has begun offering emergency subsidies of $9 to $11 an acre to help farmers pay for irrigation. Local and provincial governments are also providing financial help. Chen Shuwei, the vice president and chief analyst at Beijing Orient Agribusiness Consultant, a Beijing firm with close links to the Agriculture Ministry, said that the winter wheat crop supplied over 90 percent of the country’s supply and was typically harvested in June, with the rest grown over the summer. China is the world’s largest wheat grower, accounting for one-sixth of the world output in good years. The government has wheat stockpiles equal to half the country’s normal harvest. Beijing’s top priority this year is to fight inflation, and food accounts for a third of China’s consumer price index. China’s leadership appears to have become alarmed after Mr. Wen toured drought-stricken regions in late January and then held a cabinet meeting to discuss the problem.
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