Tim McDonnell

Tim McDonnell

Climate Desk Associate Producer

Tim McDonnell joined Climate Desk after stints at Mother Jones and Sierra magazine. He remains a cheerful guy despite covering climate change all the time. Originally from Tucson, Tim loves tortillas and epic walks.

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Step Inside the World's Largest Solar Boat

| Fri Jun. 21, 2013 1:13 PM EDT

The solar plane will land in New York City soon, but its water-borne counterpart is already here: Early this week the world's largest solar-powered boat steamed into lower Manhattan and docked in small marina, usually reserved for multimillion dollar yachts, in the shadow of the new World Trade Center tower. The three-year-old ship, dubbed "Turanor" after a term for solar power in The Lord of the Rings, is on a tour of the Atlantic from its home base in southern France, documenting how the warming sea is shifting the Gulf Stream, a powerful cross-ocean current that drives the weather of Europe and West Africa.

CHARTS: You Won't Believe How Much Disasters Cost Last Year

| Thu Jun. 20, 2013 5:14 PM EDT

2012 was the second-worst year on record for extreme weather events, both in number and in cost, according to a tally released this morning by the National Oceanic and Atmospheric Administration. Eleven major events—including tornadoes, wildfires, droughts, and hurricanes—racked up a collective bill of over $110 billion, with cropland damage from drought in the Midwest ($17.36 billion in crop insurance payments alone) and Hurricane Sandy, with a $60 billion price tag, as the most expensive items.


As for this summer, the costs are still piling on: Feed and water scarcity have shrunk the nation's cattle supply to its lowest point since 1952, pushing beef prices to an all-time high, and NOAA scientists predict that pasture conditions will likely be worse this summer than last.

According to the latest forecast, although drought conditions have dropped 21 percent from their peak last September, nearly half of the country is still in some kind of drought, with the worst conditions moving west through the summer into California and Oregon.

"The drought has definitely been pushing westward," Mark Svoboda of the National Drought Mitigation Center in Nebraska told reporters, adding that the devastating wildfires that have recently hit states like Colorado and New Mexico are "just the start." 


Svoboda added that lightning from the upcoming monsoon season in the Southwest created a particular wildfire risk in this still tinder-dry region, although Arizona and the central plains are expected to see some improvement of drought conditions, the result of a relatively wet spring:


Are Fungus-Farming Ants the Key to Better Biofuel?

| Tue Jun. 18, 2013 6:30 AM EDT

"If you have ants in your house," the great Harvard ecologist EO Wilson once said, "be kind to them." Keep this in mind the next time you want to flick one off the kitchen table: The tiny critters, which collectively weigh about as much as all of humanity, could wield a big weapon in the fight against climate change.

In the United States, corn-based ethanol is a big business, consuming 40 percent of the domestic corn crop and providing roughly 10 percent of the fuel supply, which would otherwise be dirty fossil fuels. But the practice of topping your tank off with corn is fraught with problems: Some argue that the crop should be used for food; it's sensitive to drought; and the ethanol-making process might be contributing to an E. coli epidemic, to name a few. That's why the Obama administration recently announced a plan to invest $2 billion in organic fuels that rely on things other than corn, including switchgrass and gas from cattle poo.

But this weekend, a group of scientists discovered a chemical key that could revitalize corn-based ethanol by allowing it to be made from stalks, leaves, and other bits beside the cob itself. This won't help much with the drought problem (less corn is still less corn), but it could alleviate the food vs. fuel debate and the E. coli problem when more kernels are saved to go straight to livestock. Turns out, the savior of ethanol could be the South American leafcutter ant.

Leafcutter ants make some of the largest underground colonies in the world, some with as many as 7 million residents. And, as the name suggests, many of them spend their days combing the rainforest for bits of leaves, gathering half the weight of a cow per colony every year. They carry this mass back into their tunnels and use it as fertilizer for a crop of fungus, which they then eat. Ant experts ("myrmecologists," if you care to know) have long believed that the fungus acts as a kind of external stomach for the ants, breaking down sugars in the leaves that the ants aren't equipped to handle themselves. In fact, it's not the fungus itself that breaks down the leaves, but chemical enzymes within it, and Frank Aylward, a microbiologist at the University of Wisconsin-Madison, says those same enzymes could be used to help break down corn byproducts to make fuel.

In a new study, Aylward sequenced the genome of the leafcutter ant's symbiotic fungus, and identified for the first time the exact enzymes that have evolved over millennia to efficiently break down plant material stored in the ant's underground tunnels.

Slicing Open Stalagmites to Reveal Climate Secrets

| Thu Jun. 6, 2013 4:04 PM EDT

Stacy Carolin collects samples in a Borneo cave last fall.

If you've ever visited a cave, you know the rules: Stay on the path, and keep your greasy paws off the formations. So Stacy Carolin was a bit taken aback the first time she headed into a cave not as a tourist, but as a scientist, and took a step off the beaten path. "I was a city girl back then," she recalls. "It was very muddy and slippery…and also completely pitch black." Not exactly the setting you'd expect for cutting-edge climate change research.

A few years later, Carolin, a Ph.D. student at Georgia Tech, is breaking ground in the field of paleoclimatology, the study of ancient climates, using an unconventional but increasingly prevalent tool: speleothems, a catch-all term for cave formations that includes stalagmites (remember the mnemonic: those that "mite" reach the ceiling from the floor) and stalactites (those that hold "tite" to the ceiling).

In a study released today in the journal Science, Carolin and her colleagues outline 100,000-year-old rainfall conditions in Borneo, mapped from chemical clues in cave formations there. Like most historic climate reconstructions, the goal is to compile real-life data against which to test predictive models; if scientists know how much rainfall there was in the tropics in the past, they can see how well their models are able to replicate those conditions, and tweak accordingly. But the most commonly-used "proxies" for ancient climates, including tree rings and ice cores, are notoriously inadequate in the tropics, leaving holes in scientists' geographic picture of the past and making it difficult to measure historic changes in tropical weather systems, like monsoons, which can themselves have major impacts on global climate.

Deep inside caves in Mexico, Southeast Asia, China, and other limestone-rich locales worldwide, scientists have found rich troves of data in speleothems. Researchers look for formations that have already fallen over or broken off, so as not to damage the cave, haul these back to the lab, slice them open ("like a hot dog," Carolin says), and study the ancient atoms within to discover how old they are and how much rainfall there was at different points in their past (speleothems form when rainwater drips through the limestone, picking up acid and minerals that pile up in the cave).

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