Bad news: Trees emit methane, a greenhouse gas. Good news: Some are home to bacteria that can’t get enough of it.
MANY OF TODAY’S geoscientists are carbon voyeurs. Knowing that human disregard for the carbon cycle has screwed the climate, they have kept a close eye on carbon’s hottest variants—carbon dioxide (CO 2) and methane. Both gasses trap heat on the planet through the greenhouse effect, and over a span of 100 years methane is 28 times more potent than CO2. Rigorously accounting for greenhouse gas flow is step one of building models that predict the future climate.
Some line items in the methane budget, such as pipeline leaks and cow farts, are well understood. But others are hazier. “There’s lots of gaps and uncertainties, particularly in wetlands, and inland waters,” says Luke Jeffrey, a biogeochemistry postdoc at Southern Cross University in Australia. By one 2020 tally from the Global Carbon Project, wetlands emit about 20 to 31 percent of Earth’s annual methane release—more than the amount from fossil fuel production.
But in the past decade, researchers have zeroed in on a perhaps counterintuitive source of greenhouse gas emissions: trees. Freshwater wetland trees, in particular. Trees bathing in wet or flooded soil absorb methane and then leak it through their bark. In a 2017 study, ecologist Sunitha Pangala, then at the Open University in the United Kingdom, found that trees in the Amazon were responsible for 200 times more methane than trees in other wetland forests, accounting for 44 to 65 percent of the region’s total emissions.
Does this mean trees are bad for the planet? Of course not. Trees suck carbon dioxide out of the atmosphere. And in a study published April 9 in Nature Communications, Jeffrey and his team report how trees can also be methane sinks, sheltering microbes that convert it to the less damaging CO2.
Read the full story in WIRED
The ebb and flow of rainy seasons corresponds with the hatching of millions of mosquitoes—and the spread of diseases they carry
Few natural phenomena pose a greater threat to humans than a swarm of mosquitoes erupting from a cluster of soil-lodged eggs. These bloodthirsty menaces can carry a host of diseases, such as Zika, West Nile and malaria, making mosquitoes the world’s deadliest animals.
Mosquito-borne diseases threaten billions of people, and while the diseases vary in biology and geography, most, if not all, are exacerbated by climate change. Scientists predict that a warming world will invite the spread of more mosquitoes, and more illness, threatening a billion more people over the next 60 years. But long-term predictions are hard to act on, and public health experts believe short-term forecasts could better kick-start programs to save people’s lives today.
For the last 20 years, scientists studying weather patterns have pieced together how real-time data can help predict mosquito-borne disease outbreaks weeks or even months before the insects emerge from the ground. These tools may provide a mechanism to prevent millions of deaths, tracking monsoons and other rain cycles to forecast mosquito hatching events.
Read the full story in Smithsonian
Bugs like it hot, and evolve faster when there’s lots of carbon dioxide
We often think of climate change in terms of extreme weather, but the impacts of global warming will extend far beyond natural disasters. Scientists suggest climate change will also make more of the world hospitable to mosquitoes—and the diseases they carry. To make matters worse, new research shows that climate change may also be supercharging mosquito evolution.
Zika, West Nile, and dengue are just a few of the deadly viruses that depend on mosquitoes to spread. Human diseases like these are also carried by animals like birds and rodents, who don’t always show symptoms. But if a mosquito bites an infected animal, it can later transmit the disease to other animals, including humans. That’s why many disease prevention efforts focus on controlling mosquito populations—a task that’s about to become a lot harder.
Read full story in Massive Science
Republished in Pacific Standard Mag
Diseases and disasters
The recently announced Green New Deal, a resolution to help address the threats of climate change, gives public health advocates a chance to confront an overlooked consequence of climate change: worsening mosquito-borne illnesses.
The resolution, which outlines projects designed to boost renewables, reduce emissions, and climate-proof the country’s infrastructure, was introduced by Rep. Alexandria Ocasio-Cortez (D-NY) and Sen. Ed Markey (D-MA). Its goal is to extinguish potential economic, national, and social infernos that are brought on by climate change. But the plan also recognizes growing threats to public health, such as the diseases becoming far more common in a warming world.
Climate change has already expanded the reach of mosquitoes that carry certain illnesses. More extreme weather events are also part of the package, and more severe storms, stronger hurricane seasons, more floods and droughts also increase the risk of disease after a natural disaster. According to the World Health Organization (WHO), climate change could increase the number of people who are at risk of malaria by over 100 million.
Read more in The Verge