A tropical storm is brewing in the Atlantic Ocean. It’s causing rain and thunderstorms over the Caribbean, and it will soon be a tropical depression — the beginning of a hurricane. By the time Hurricane Mitch leaves the Central America, more than 11,000 people will be dead and as many as 18,000 more will be missing. (Activity adapted from Mapping Our World at http://edcommunity.esri.com/MOW.)
Even though our home planet has a lot of water, over 73 percent of that is salt water. We need freshwater to meet most of our needs, and precipitation supplies much of this valuable natural resource. Did you know that NASA, in a partnership with the Japanese, has a satellite that measures precipitation as it falls from the clouds to the ground?
No matter where we are on Earth, we can observe changes in vegetation. Some changes are drastic, such as going from dormant to full growth during a temperate winter.
Vegetative growth is dependent on both surface temperature (which influences soil temperature) and precipitation (which influences soil moisture). Together these environmental variables help determine the beginning, duration, and end of the growing season; the latter marked by leaf senescence, when leaves of deciduous trees die and turn colors.