DETROIT -

People have been asking me if last week’s historic flood was caused by global warming. 

The short answer is NO, but read on because this answer requires an explanation. 

Weather systems develop all the time, and have been doing so for as long as we’ve had weather on this planet.  The weather system that developed and dumped a once-every-500-year rain event on metro Detroit last week may have developed anyway. 

HOWEVER, our warming climate might have made that weather system a heavier rain-producer than it might have been. 

Here’s why:  as our planet warms, a greater amount of ocean water evaporates into the atmosphere. Since water vapor is the moisture that storms tap into to produce precipitation, more of that available water vapor in the atmosphere means that higher intensity precipitation events are more likely. It is documented fact that our planet’s atmospheric humidity has increased in synch with the warming temperatures, and every climate scientist that I’ve ever spoken to says that this will lead to more extreme weather events. And that’s exactly what’s happening. 

So, if somebody tells you that the storm that caused the Great Flood of 2014 was caused by global warming, that’s wrong.  However, there is truth to the statement that global warming could have enhanced the amount of rain that the storm produced.