A Vegetation Greenness "Difference" Map
| Farmers and crop producers spend a lot of time in their fields, and remember how their crops were doing the previous year and use this knowledge as a reference for gauging how well their crops are performing this year. To give growers a tool for making these kinds of comparisons over larger areas, modeling is used to compare the current crop conditions (NDVI values) with the conditions from the year earlier. This produces a map called Greenness Difference Map 2. In this example, crop conditions from mid-July, 2000 were compared to crop conditions from early-July, 1999. Dark green areas show crops that are more developed compared to the previous year, while yellow areas show vegetation that is not as green as the previous year. In this map, the spring wheat in area 1 and the corn and soybeans in area 2 are all developing ahead of last year's rate. The mixed croplands in the southern parts of area 3 are developing ahead of last year, while the northern parts are developing at the same rate. |
Credit: Kansas Applied Remote Sensing/NASA
For more info: http://www.kars.ukans.edu/products/greenreport.htm