Lightning strikes: Thunderstorms spread mercury pollution

August 31, 2016

TALLAHASSEE, Fla. -- In the southern United States, an afternoon thunderstorm is part of a regular summer day. But new research shows those storms might be doing more than bringing some scary thunder and lightning. In fact, these storms are moving significant amounts of mercury to the ground.

In a new study published in the journal Environmental Science and Technology, Assistant Professor of Meteorology Christopher Holmes writes that thunderstorms have 50 percent higher concentrations of mercury than other rain events.

"The mercury is being transported into our region by winds, and tall thunderstorms are bringing it down to the earth," Holmes said.

Holmes and a team of researchers collected rain in a variety of locations in Florida, as well as Vermont, Georgia and Wisconsin. They then matched it to weather data that told them whether it was from a thunderstorm or just rain. They also used radar and satellite data to examine storm clouds.

In a regular rainstorm, clouds are only a few kilometers thick. In a thunderstorm, they reach about 15 kilometers thick. Researchers found that more mercury was in rain from the clouds that reached the highest altitudes.

"The highest concentrations occurred during thunderstorms and the lowest during a regular rainstorm," Holmes said.

For the last 20 years, the Mercury Deposition Network has recorded mercury content of precipitation across the United States. During this period, the states bordering the Gulf of Mexico have consistently seen the highest mercury deposition in the eastern U.S., typically double that of the northeast states.

Typically, the Southeast sees a high number of thunderstorms in the summer months. Holmes and his colleagues believe that this is the reason the Southeast has higher levels of mercury in rain.

Mercury is a naturally occurring chemical element that is used in several devices such as thermometers, barometers, fluorescent lamps and other devices. Exposure to high levels of mercury can be dangerous though.

Holmes said now that researchers know that the storms are spreading the mercury, they need to understand why there are high amounts of mercury at these higher altitudes and how it affects the Earth.

"We're trying to understand how mercury enters ecosystems in the U.S. and how it can affect people and wildlife," Holmes said.
-end-
Holmes' co-authors on the project are FSU graduate student Nishanth Krishnamurthy and FSU Professor William Landing; Jane Caffrey from the University of West Florida; Eric Edgerton from Atmospheric Research & Analysis Inc.; Kenneth Knapp from the National Oceanic and Atmospheric Administration; and Udaysankar Nair from the University of Alabama.

The work was supported by Florida State University, the Electric Power Research Institute and the U.S. Environmental Protection Agency.

Florida State University

Related Mercury Articles from Brightsurf:

Mercury's 400 C heat may help it make its own ice
Despite Mercury's 400 C daytime heat, there is ice at its caps, and now a study shows how that Vulcan scorch probably helps the planet closest to the sun make some of that ice.

New potential cause of Minamata mercury poisoning identified
One of the world's most horrific environmental disasters--the 1950 and 60s mercury poisoning in Minamata, Japan--may have been caused by a previously unstudied form of mercury discharged directly from a chemical factory, research by the University of Saskatchewan (USask) has found.

New nanomaterial to replace mercury
Ultraviolet light is used to kill bacteria and viruses, but UV lamps contain toxic mercury.

Wildfire ash could trap mercury
In the summers of 2017 and 2018, heat waves and drought conditions spawned hundreds of wildfires in the western US and in November, two more devastating wildfires broke out in California, scorching thousands of acres of forest, destroying homes and even claiming lives.

Removing toxic mercury from contaminated water
Water which has been contaminated with mercury and other toxic heavy metals is a major cause of environmental damage and health problems worldwide.

Fish can detox too -- but not so well, when it comes to mercury
By examining the tissues at a subcellular level, the researchers discovered yelloweye rockfish were able to immobilize several potentially toxic elements within their liver tissues (cadmium, lead, and arsenic) thus preventing them from interacting with sensitive parts of the cell.

Chemists disproved the universal nature of the mercury test
The mercury test of catalysts that has been used and considered universal for 100 years, turned out to be ambiguous.

Mercury rising: Are the fish we eat toxic?
Canadian researchers say industrial sea fishing may be exposing people in coastal and island nations to excessively high levels of mercury.

New estimates of Mercury's thin, dense crust
Michael Sori, a planetary scientist at the University of Arizona, used careful mathematical calculations to determine the density of Mercury's crust, which is thinner than anyone thought.

Understanding Mercury's magnetic tail
Theoretical physicists used simulations to explain the unusual readings collected in 2009 by the Mercury Surface, Space Environment, Geochemistry, and Ranging mission.

Read More: Mercury News and Mercury Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.