July 4th: Environmental Dangers and Celebration

July 4th is a day of extremes:  one of celebration, barbecues, and holiday for many, on one hand.

And substantial environmental dangers on the other:  wildfires, degraded air quality, lost pets, and injury. 

A little care can reduce the dangers considerably, most of which are associated with the personal use of fireworks.   

Let me start by showing you the average number of fires per day over Washington State, for the period from 1992 to 2015, provided by Josh Clark of Washington State's Department of Natural Resources.

First, here is a plot of all fires from all causes.  A huge spike on July 4th...the biggest fire initiation day of the year.   Wonder why.

In case,  you are in suspense, the plot for human-caused fires is below...July 4th is dominant.

The most important cause of natural fires is lightning, and here is the plot.  Peak lightning fire initiation is in late July and early August when the ground has dried and the surface temperatures are the highest.

Next, lets consider air quality.  The combination of large community fireworks display and thousands of "private" shows results in a huge degradation of air quality late on July 4th and the morning of July 5, particularly in urban areas. 

To illustrate this, take a look at a key air quality measurement (small particles that can move deep into your lungs, known as PM2.5) for Seattle's Beacon hill for July 2-8, 2017.  Values surged to over 140, which is very unhealthy for vulnerable populations.  Other major cities and fireworks locations showed similar July 4 peaks.

What about injuries?  Thousands of people are burned, lose fingers, damage their eyes, and experience other traumas due to fireworks, many of them teenage boys.  Here is a graph from the Journal of Surgical Research showing the number of hospital visits due to fireworks injuries (and I bet many more injuries are not reported).  July 4th fireworks obviously play a major role.

And then there is the terror that fireworks incite in domestic pets and wildlife.  July 5th is historically the busiest day of the year at pet shelters.  Many pets never return home.

So what is the current situation on the ground and the forecast for July 4th?  The latest wildfire danger map from Washington DNR shown high danger in much of eastern Washington, with moderate danger in the Columbia Gorge.

The latest forecasts are for a warming trend tomorrow (July 4), with low to mid 80s in much of western Washington away from the water.  We expect considerable cloudiness, particularly during the later part of the day. 

So decent weather to enjoy public fireworks.   And a good time to avoid igniting fireworks yourself.



from Cliff Mass Weather and Climate Blog https://ift.tt/2za7dZe