Lightning strikes more than 100 million times per year in the tropics

July 23, 2020

Researchers at the Smithsonian Tropical Research Institute (STRI) in Panama have published dramatic maps showing the locations of lightning strikes across the tropics in Global Change Biology. Based on ground and satellite data, they estimate that more than 100 million lighting strikes on land each year will radically alter forests and other ecosystems in the region between the Tropic of Cancer and the Tropic of Capricorn.

"Lightning influences the ability of forests to store biomass, and therefore carbon, because it tends to strike the largest trees," said Evan Gora, a post-doctoral fellow at STRI who recently finished his doctorate at the University of Louisville. "And lightning strikes may also be very important in savanna ecosystems."

Because lightning is so challenging to study, it has been overlooked as a change-agent in tropical forests where researchers focus their energy on more obvious disturbances like drought, fire, and high winds.

In a previous study, the first to examine the effects of lightning on a tropical forest landscape, the same team found that lightning probably kills half of the biggest trees in a Panamanian forest. Tropical ecologist Steve Yanoviak, study coauthor and professor at the University of Louisville who was studying ants in the tropical forest canopy--and often thought about the role of lightning while climbing trees, invited lightning researchers Jeffrey Burchfield and Phillip Bitzer from the University of Alabama at Huntsville to set up lightning detectors at STRI's Barro Colorado Island Research Station.

"We found that a lightning strike damages a total of 23.6 trees and kills 5.5 of these trees within a year, on average," Yanoviak said.

Now the team is asking how lightning affects tropical ecosystems everywhere. Gora led the effort to map lightning strike counts based on images from the Earth Networks Global Lightning Network (ENGLN) onto a map of tropical ecosystems created using land-cover categories from the International Geosphere-Biosphere Program and the Moderate Resolution Spectroradiometer (MODIS) Land Cover Climate Modeling Grid.

Based on satellite data about strike locations and on-the-ground effects around 92 lightning strikes, including many from the previous study, Gora and his colleagues estimated that lightning damages approximately 832 million tropical trees each year. Roughly a quarter of the trees probably die from their injuries.

Gora and colleagues then asked whether there was a connection between the number of lightning strikes and the type of ecosystem, its biomass and climate variables like rainfall and temperature. They found that lightning strikes were more frequent in forests, savannas and urban areas than in grasslands, shrublands and croplands.

Forests that experience more lightning strikes each year have fewer large trees per hectare, perhaps because the large individual trees in these forests stand out more, higher rates of woody biomass turnover (more tree biomass dies each year) and less total aboveground biomass.

But more burning questions remain. No one knows why some trees survive lightning strikes while others die, although it is likely that trees have evolved ways of coping with such a common threat.

And, as climate change accelerates, polluted, hot air over cities may also increase the number of lightning strikes there. What will the effects be on vegetation in urban areas?

"This is the best evidence to date that lightning is a major disturbance influencing tropical forest dynamics and structure," said STRI staff scientist and study co-author Helene Muller-Landau, "We suspect that our study vastly underestimates the total effect of lightning. Lightning strikes may play a major role in forest biomass/carbon cycling not only in tropical forests but also in other tropical ecosystems."
-end-


Smithsonian Tropical Research Institute

Related Biomass Articles from Brightsurf:

Bound for the EU, American-made biomass checks the right boxes
A first-of-its-kind study published in the journal Scientific Reports finds that wood produced in the southeastern United States for the EU's renewable energy needs has a net positive effect on US forests--but that future industry expansion could warrant more research.

The highest heat-resistant plastic ever is developed from biomass
The use of biomass-derived plastics is one of the prime concerns to establish a sustainable society, which is incorporated as one of the Sustainable Development Goals.

Laser technology measures biomass in world's largest trees
Laser technology has been used to measure the volume and biomass of giant Californian redwood trees for the first time, records a new study by UCL researchers.

Inducing plasma in biomass could make biogas easier to produce
Producing biogas from the bacterial breakdown of biomass presents options for a greener energy future, but the complex composition of biomass comes with challenges.

Microbes working together multiply biomass conversion possibilities
Non-edible plants are a promising alternative to crude oil, but their heterogenous composition can be a challenge to producing high yields of useful products.

Evergreen idea turns biomass DNA into degradable materials
A Cornell-led collaboration is turning DNA from organic matter -- such as onions, fish and algae -- into biodegradable gels and plastics.

Upgrading biomass with selective surface-modified catalysts
Loading single platinum atoms on titanium dioxide promotes the conversion of a plant derivative into a potential biofuel.

A novel biofuel system for hydrogen production from biomass
A recent study, affiliated with South Korea's Ulsan National Institute of Science and Technology (UNIST) has presented a new biofuel system that uses lignin found in biomass for the production of hydrogen.

Biomass fuels can significantly mitigate global warming
'Every crop we tested had a very significant mitigation capacity despite being grown on very different soils and under natural climate variability,' says Dr.

Traditional biomass stoves shown to cause lung inflammation
Traditional stoves that burn biomass materials and are not properly ventilated, which are widely used in developing nations where cooking is done indoors, have been shown to significantly increase indoor levels of harmful PM2.5 (miniscule atmospheric particulates) and carbon monoxide (CO) and to stimulate biological processes that cause lung inflammation and may lead to chronic obstructive pulmonary disease (COPD), according to new research published online in the Annals of the American Thoracic Society.

Read More: Biomass News and Biomass 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.