Scientists have found that observed changes in global precipitation are directly affected by human activities. The Lawrence Livermore National Laboratory have determined that global ocean and land precipitation can’t be explained by natural variability alone. Human emissions can have an effect on precipitation in two ways. Increase of global temperatures will make wet regions wetter and dry regions drier. It will also cause change in atmospheric circulation patterns, causing storm tracks and subtropical dry zones to move closer to the poles. Although natural occurrences such as El Nino or La Nina can cause this to happen naturally, the previous two effects of human emissions on precipitation cannot happen together naturally. This is strong evidence that humans are in fact affecting global precipitation.
– Sean Sabogal –