People often use the terms “climate change” and “global warming” interchangeably, but it is important to note that climate encompasses more than just temperature.  A climate refers to the weather conditions in a specific geographic region, which of course includes temperature, but also has a great deal to do with precipitation.

When we think about our water supply, precipitation is key.  In the case of New York City, the amount of precipitation we get locally does not actually matter too much.  All of our water comes from the Catskill/ Delaware Watersheds in upstate New York.  So, the precipitation we are concerned with is in a region designated by NOAA as Climate Division 2 of New York.

As seen in the accompanying graph, the region in which the watersheds are contained gets a lot of water.  The reservoirs are full, and there is no imminent threat of that changing.  However, we must keep in mind that year-to-year accumulation is variable, and precipitation events are erratic.  For example, in 2011 there was a huge spike in precipitation from Hurricane Irene.

Although New York City’s water supply is in good shape for the foreseeable future, the looming Delaware Aqueduct shutdowns can cause delivery issues.