The March – April 2018 issue of Skynews shows how NASA satellites can differentiate a variety of contaminants in the upper atmosphere.
Terrance Dickinson describes how the August and September images from last year show various particles carried by prevailing winds.
Smoke from British Columbia megafires appears white and stretches from B.C. well into the Pacific and Atlantic oceans, brown dust clouds are clearly seen coming off the Sahara desert and blue sea salt clouds are found in most of the major oceans.
Dickinson, who is a well known author and astronomer living in Kingston, Ont., first noticed an impact of B.C. wild fire smoke on the quality of eastern skies in the fall of 2017.
As he notes this continent-wide smoke haze has happened before.
In the summer and early fall of 1950 massive wildfires in B.C. created huge amounts of smoke which the newspapers of the day dubbed the “great smoke pall” which extended across eastern North America and Europe.
While satellites allow us to determine the extent of wildfires since the 1970s, I am not sure if it is possible to determine if the 1950 fires were as extensive as those last year.
Even before we had satellites to monitor the atmosphere contamination it was pretty obvious in some situations.
Stories and pictures of the massive dust clouds produced by poor farming practices in the prairie grasslands of central USA during the dirty thirties sent fine dust particles high into the air that ended up on the east coast of the states and even landed on ships far out into the Atlantic Ocean.
Some of atmospheric contamination may only be an annoyance for a short time and some may have longer-term consequences like the radiation cloud from the Chernobyl meltdown.
Author John Calderazzo in the book Bedrock describes how it was once thought that fine volcanic ash sent into the upper air layers was similar to wildfire fire smoke but a near air disaster in Alaska in 1989 proved the volcanic ash is much different.
A nearly brand new 747 jumbo jet flying from the Netherlands to Tokyo was scheduled to refuel in Anchorage when it ran into a volcanic dust cloud produced by the Mount Redoubt eruption which was over 200 miles away from their flight path.
While the cloud that the airline encountered at five miles altitude appeared normal there were immediate impacts as they entered it at over 500 mph.
There was instant darkness in the cockpit and the acrylic wind screens were quickly eroded by the hard sharp dust particles and the fine dust filled the plane.
The pilots tried to climb out of the cloud but didn’t realize the deadly particles had risen to over seven miles above sea level.
Soon all four engines stopped and the plane went into a five minute free fall before they were able to clear the cloud and restart the engines after eight tries.
During the free fall anything that was not tied down began to float throughout the plane (pens, pencils pillows etc.).
The good news is the plane was able to land safely with no (physical) injuries to the passengers and crew but the bad news was there was over $80 million dollars of damage to the plane which was grounded for months.
The deadly cloud did thin out as it moved south but some pilots noticed the corrosive sand like particles as far south as Texas a few days later.
Jim Hilton is a professional agrologist and forester who has lived and worked in the Cariboo Chilcotin for the past 40 years. Now retired, Hilton still volunteers his skills with local community forests organizations.