New study shows surprising effects of fire in North America’s boreal forests
A new study, using a first-of-its-kind approach to analyze satellite imagery from boreal forests over the last three decades, has found that fire may be changing the face of the region in a way researchers did not previously anticipate.
Historically, fires in North American boreal forests have led to coniferous trees being supplanted by deciduous trees, which are faster growing, take up more carbon and reflect more light, leading to cooling of the climate and decreased likelihood of fire.
The study, led by Northern Arizona University and published today in Nature Climate Change, found that surprisingly, while forests do become more deciduous, they don’t stay that way; a few decades later, the same forests gradually start to shift back toward coniferous trees.
Cranberry growers are bringing wetlands back from the dead
In Massachusetts, the onetime cranberry capital of the world, former bogs are transforming into thriving, carbon-storing swamps.
When Glorianna Davenport and her husband, Evan Schulman, decided in the early 2000s to stop growing cranberries after two decades in the business, they were left with a difficult choice. They could sell their land, parts of which had been farmed for well over a century, to a developer and watch it be “chopped up into small lots,” as Davenport puts it. Or they could fight to keep it whole.
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From the Silo – The Road to COP 28: Episode 2
The first episode in our series leading up to the COP28 summit in November will be distributed in two parts. This episode, called the Road to COP28, features the second half of a roundtable conversation hosted by Rachel Kyte, Dean Emerita of the Fletcher School at Tufts University. Senator Ben Cardin from Maryland also joins the conversation to share his insight on the COP event and efforts to address climate issues in the US Senate. Our panel of experts includes Professor at the University College London Mark Maslin, Interim Chair of the IUCN Climate Crisis Commission Manuel Pulgar-Vidal, Director of the NASA Goddard Institute for Space Studies Gavin Schmidt, Chief of Government Relations at the Woodwell Climate Research Center David McGlinchey, and Co-Founding Dean Emerita of the Columbia Climate School Ruth DeFries. Their conversation sets the stage for what needs to be done at the upcoming COP 28 conference, and foreshadows what real policy changes, if any, may come as a result. Join us for this extremely critical discussion.
If the summer of 2023 felt abnormally hot to you, that’s because it was. With heat waves making headlines month after month, this year saw a spike in temperatures that broke global records.
September 2023 followed in the footsteps of both August and July as the hottest each month has been since temperature record-keeping began, making the late summer of 2023 Earth’s hottest yet. Here’s how 2023’s sweltering heat compares to past years:
- Global average surface air temperature reached a record high in the summer of 2023.
- July 24th, 2022 was the hottest day of last year, at 62.5 degrees F.
- July 3rd, 2023 was the first day that was hotter than the hottest day in 2022.
- July 6th, 2023 was Earth’s hottest day on record.
- 42 days this year were hotter than the hottest day in 2022.
Record-breaking heat in 2023
In North America alone, 78 all time records for hottest temperature were broken over the course of June, July and August. In New Iberia, Louisiana, the temperature record was broken four times, peaking at 109 degrees F. Places as far north as Wainwright Airport in Alaska saw temperatures as high as 84 degrees.
Humidity makes the heat deadly
Extreme heat events like these present a serious danger to human health. That threat is multiplied when instances of high temperature coincide with high humidity— interrupting the ability of the human body to cool off through evaporating sweat. A recent paper, co-authored by Woodwell Climate Risk Program director, Dr. Christopher Schwalm, defines “lethal heat” as a wet bulb temperature (a measure combining heat and humidity) of 35 degrees C (95 degrees F). Prolonged exposure— over 6 hours— to temperatures exceeding this can result in death even for a healthy person keeping hydrated in the shade
According to the paper, instances of deadly heat waves are increasing with climate change. Already, with over a degree of warming, parts of Northern India are seeing annual heat events. By just two degrees of warming— a milestone we are currently on track to hit by mid-century— a quarter of the world is expected to experience a lethal heat event at least once in a decade. A significant subset of the world, particularly regions of India, Africa, South America, and the Southeastern US, can expect deadly heat conditions at least once a year at that point, and the area will expand wider with each half degree of warming.
It’s a forecast that highlights the urgency of acting to mitigate warming and developing local and regional strategies to prepare communities to handle high heat and humidity events when they do come.
“It puts this past year’s heat waves into somber perspective,” says Dr. Schwalm. “Without action, we put a lot more, potentially billions, of people at risk of heat stress or death on an annual basis. It’s a significant public health concern.”
Record-breaking wildfires blanket Brazil with smoke
The blazes comes on top of a drought that has left some river communities stranded.
A record-breaking number of wildfires are blanketing the Amazon with smoke, choking some Brazilian cities and further isolating many Indigenous villages. Over 2,700 wildfires have been reported in the region in the first 11 days of the month — the highest number for any October since 1998, when the record-keeping began.
Air quality became so poor last week in places like Manaus that officials had to postpone the city’s annual marathon, and major universities canceled classes. Philip Fearnside, research professor at the National Institute for Research in Amazonia, said hospitals in the city are full of people who are having respiratory issues. “That should be a wake up call to actually change government policies and individual behavior to actually contain global warming,” he said.
World breaches key 1.5C warming mark for record number of days
The world is breaching a key warming threshold at a rate that has scientists concerned, a BBC analysis has found.
On about a third of days in 2023, the average global temperature was at least 1.5C higher than pre-industrial levels.
Staying below that marker long-term is widely considered crucial to avoid the most damaging impacts of climate change.
But 2023 is “on track” to be the hottest year on record, and 2024 could be hotter.