Tim McDonnell

Tim McDonnell

Climate Desk Associate Producer

Tim McDonnell joined the Climate Desk after stints at Mother Jones and Sierra magazine, where he nurtured his interest in environmental journalism. Originally from Tucson, Tim loves tortillas and epic walks.

Get my RSS |

WATCH: Why Carbon Pollution Is Destroying the Ocean

| Fri Sep. 27, 2013 2:52 PM EDT

One of the major themes in today's report from the Intergovernmental Panel on Climate Change is the significance of oceans, which absorb 30 percent of the carbon dioxide we emit. This turns the water increasingly acidic, which threatens to dissolve many marine critters' hard shells. I sat down with Monika Rhein, an oceanographer at Germany's University of Bremen and a lead author of the IPCC report's chapter on oceans, to talk about the state of the science on ocean acidification.

Advertise on MotherJones.com

World Scientists Put Finishing Touches on Major Climate Report

| Thu Sep. 26, 2013 12:10 PM EDT
Activists erect a tribute to melting ice outside the IPCC's meeting hall in Stockholm.

Today, on a walkway above Stockholm's Riddarfjärden bay, four activists in red jumpsuits wrestled with three 2,400-pound chunks of ice. The ice, which will melt onto the sidewalk over the next two days, is meant as a reminder of melting glaciers above the Arctic Circle some 700 miles north of here—although this particular ice was hand-delivered by the same company that maintains Sweden's famous ice hotel. A few steps away, dozens of top climate scientists from across the globe were sealed in a conference room inside an imposing brick compound that was once one of the city's largest breweries. They've come to hash out last-minute details of the UN Intergovernmental Panel on Climate Change's Fifth Assessment Report, the last day of a week of tweaks and edits to cap off over five years of work.

"We want to show that the climate change is real," one of the activists, Valentina Restrepo, said. She's not likely to face much resistance to that argument from the women and men behind the report: A leaked draft stated that global warming is "extremely likely" (or 95 percent certain) to be caused by human activities. When the report is officially released tomorrow morning, it will be the IPCC's first global assessment of the state of climate science since 2007, and it's expected to include updates on everything from how long carbon dioxide hangs out in the atmosphere, to the  dangers posed by sea level rise, to the alleged "slowdown" in warming many climate skeptics have trumpeted in recent weeks.

meeting hall
Stockholm's Münchenbryggeriet, a former brewery where dozens of the world's top climate scientists gathered this week to put the finishing touches on the next IPCC report. Tim McDonnell/Climate Desk

But one question we'll be asking scientists tomorrow goes beyond the science itself: Is a report like this really necessary? A criticism voiced by many scientists, both within and outside of the IPCC, is that while early iterations of the report were essential tools for alerting policymakers to the dangers of climate change, this fifth report is unlikely to differ significantly from the last report six years ago (which won a Nobel Prize for laying "the foundation" for climate solutions), calling into question the value of dedicating time and resources to re-producing it in its current format.

“If it were up to me, there would not be an AR6 (Sixth Assessment Report),” atmospheric scientist Andrew Dessler told our friends at Climate Central.

There is no original science conducted for these reports; instead, scientists meticulously aggregate, review, and summarize existing literature. While that sounds like a worthwhile endeavor in theory, the amount of time required means that some science (like, as my colleague Chris Mooney reported, on the effects of warming on hurricanes) might be already obsolete by the time it comes out.

Of course, the policymakers who rely on the IPCC to inform their practical approaches to climate change aren't suggesting that the group disband, but rather break the massive report into more manageable and regularly-issued chunks, according to a survey of participating countries the IPCC conducted earlier this year. This way, the government bureaus that deal with, say, ocean issues, wouldn't have to sift through a stack of papers on volcanoes to find what's relevant for them. A new format is one thing that'll be on the table when members of the group re-convene in Batumi, Georgia, next month.

No matter what form the report takes in the future, its top-line findings tomorrow will form the backbone of climate talking points for at least the next five years, and in Stockholm the coffee is flowing as scientists gear up for a long night of finishing touches (into the "early a.m.," one wrote to us). Climate Desk will be on the scene all day tomorrow, with live updates from IPCC scientists and other analysis, so stay tuned.

Is Climate Change Pushing Pests into Northern Farms?

| Sun Sep. 1, 2013 1:00 PM EDT

Pine beetles like this aren't the only pests driven north by climate change.

In 1996 Colorado received a very unwelcome—and hungry—house guest, the mountain pine beetle, whose voracious appetite for pine has since killed off millions of acres of trees there. A few years later, the beetles came knocking in British Columbia and have now knocked out over half the province's pine timber. The full-bore invasion of these critters, each no bigger than a grain of rice, is now one of the most pressing ecological disasters in the West, and their spread, scientists believe, is driven by climate change.

The beetles aren't alone: Rising equatorial temperatures have pushed a menagerie of pests north at an alarming rate of nearly 10,000 feet every year since 1960, according to a new survey out today in Nature. Researchers led by biologist Dan Bebber at the UK's University of Exeter combed through databases hosted by the non-profit CABI, which aggregates scientific and trade literature on agriculture, for the first documented appearance of over 600 kinds of pests (including insects, fungi, viruses, and bacteria), over a 50-year period in the Northern Hemisphere. They found, averaged across 14 taxonomic groups, a distinctive northward migration, wherein species first noticed at southern latitudes were, at a later date, discovered anew at northern latitudes. 

The chart below, from the paper, shows the distribution range of the different pest groups Bebber examined, with the vertical axis indicating distance from the equator (positive distances indicate north; negative distances indicate south) and the horizontal axis indicating time, from 1960 to the present. Overall, the groups show a gradual northward migration over time (up and to the right):

pest distribution chart
Bebber et al.
Fri May. 9, 2014 7:07 PM EDT
Thu Mar. 27, 2014 6:00 AM EDT
Thu Mar. 20, 2014 1:39 PM EDT
Thu Mar. 13, 2014 2:26 PM EDT
Fri Feb. 7, 2014 7:00 AM EST
Fri Jan. 31, 2014 5:04 PM EST
Thu Jan. 16, 2014 11:40 AM EST
Tue Nov. 12, 2013 7:00 AM EST
Sun Nov. 10, 2013 2:00 PM EST
Tue Oct. 22, 2013 3:41 PM EDT
Tue Oct. 15, 2013 4:12 PM EDT
Mon Oct. 14, 2013 6:00 AM EDT
Fri Sep. 27, 2013 3:00 PM EDT
Fri Aug. 9, 2013 6:00 AM EDT
Tue Aug. 6, 2013 3:49 PM EDT
Mon Jul. 1, 2013 1:38 PM EDT
Tue Jun. 25, 2013 11:56 AM EDT
Fri Jun. 21, 2013 1:13 PM EDT