Abstract
Remote sensing by a satellite started in 1960. After that, many kinds of satellites have been launched to observe the global environment. We can use a huge amount of data on the global environment gathered by satellites today. Remote sensing using satellites is also a powerful tool to estimate crop production. This method can be used from local scale to global one. Long-term crop changes caused by global warming as well as the annual crop estimation before harvest have been examined using satellite images. The planting area is important to estimate a short-term crop. Changes of arable land areas and their productivity caused by global warming are significant for the long term estimation. We focused the production estimation of major cereals, i.e., rice, wheat and maize. The problems in which we are facing to get more reliable estimation and strategies for further studies are discussed in this paper.
