Saharan Dust makes its way into North Texas
NBC Universal, Inc.
A plum of Saharan dust has made its way into North Texas. This will make the skies hazy, especially during the morning and evening hours. More plumes of dust are coming off the western coast of Africa and headed toward the United States. This dust event is something that happens every year, usually around late June and early July.
WHAT IS SAHARAN DUST?
Saharan dust, also called the Saharan Dust Layer (SAL), are outbreaks of dust from the Sahara Desert in Africa that have been kicked up into the air from tropical waves in Atlantic Ocean. At miles above the atmosphere, this layer of dust is about 2 to 2.5 miles thick.
Although there are no health hazards associated with the dust, the dust may be irritating for those with allergies or lung issues. Those with breathing issues are advised to stay indoors or limit outdoor exposure on days with higher dust concentrations.
IMPACT ON THE TROPICS
The warmth, dryness and strong winds associated with these dust plumes, have been shown to suppress tropical development.
First, Saharan dust is very warm. This warmth can stabilize the atmosphere by suppressing cloud formation.
Second, Saharan dust is extremely dry air that has 50% less moisture than a typical tropical airmass. This extreme dry air can weaken a tropical system by promoting downdrafts around the storm.
And third, Saharan dust is a signal of strong jet stream winds. These winds can increase the vertical wind shear in and around the storm environment. This will cause a disruption in the development of a tropical system.
NICE SUNRISES AND SUNSETS
Normally when the sun is lower in the sky, the light travels through more atmosphere. As this happens, it scatters the shorter wavelength colors such as blue, purple and green. This allows the longer wavelength colors such as orange, pink and red, to reach the human eye.
Add Saharan dust to the atmosphere and its tiny minerals not only act to block some sunlight, but they also reflect it and scatter the colors even more.
The additional scattering will create more vivid hues of reds, oranges, pinks, yellows and even purples. Thus, nice sunrises and sunsets are visible across North Texas.