Biological processes are complex and influenced by low-energy sources, and therefore they are sensitive to small fluctuations of the environment which are related to solar influence, meteorology, and even cosmic rays. Ecosystems involving plants and animals have been built in a long period of adaptation to specific climates. If the parameters evolve rapidly, either globally or locally, the adaptation processes may not follow, and the disruption can lead to species extinctions, as already happened after cataclysmic volcanic eruptions or collisions with asteroids. Diseases are also part of this ecosystem, as their agents and vectors are dependent on meteorological parameters. This chapter shows some recent examples of epidemiological forecasts and pest studies based on satellite Earth observation.