Extreme weather events more likely even if climate change is curtailed

Parched soil in Illinois during the 2012 drought. (Thought Quotient/flickr)
Jenna Ladd | February 22, 2017

A study recently published in the journal Science Advances found that even if global climate change mitigation goals are met, extreme weather events will still occur more frequently in the future.

The United Nations Paris Climate Accord aims to keep global temperatures from increasing more than two degrees Celsius above pre-industrial levels. Even if the global community succeeds, human-induced climate change has already made extreme heatwaves, floods and droughts significantly more common.

Unfortunately, scientists say that the existing emission-reduction pledges by the world’s nations are not enough to keep temperatures from rising above 2 degrees Celsius. The study finds that if temperatures were to rise to 3 degrees hotter than preindustrial levels, North America would see at least a 300 percent increase in extreme weather events, for example.

Dr. Noah Diffenbaugh is a climate scientist at Stanford University and the study’s lead author. He said to the Scientific American, “In addition to not meeting the global temperature target, those commitments also imply substantial increase in the probability of record-setting events. Not only hot events but wet events, and also in other regions of the world, dry events as well.”

The study found that extreme heat records are the most likely to be affected by unabated climate change. Scientists focused primarily on North America, Western Europe and East Asia. They found that hotter-than-ever night time temperatures have been occurring much more frequently in recent years. If the climate warms to the 3 degree threshold, extreme heat events are expected to happen five times more frequently in half of Europe and at least three times more frequently in parts of Eastern Asia.

The study reads, “However, even if cumulative emissions are sufficiently constrained to ensure that global warming is held to 1° to 2°C, many areas are still likely to experience substantial increases in the probability of unprecedented [extreme weather] events.”

An interactive map created by researchers at Carbon Brief allows user to see which past extreme weather events can were cause by anthropogenic climate change and which were not.

Link between climate change and conflict questioned

The relationship between climate change and conflict has been studied in Kenya more than many other nations. (Viktor Dobai/flickr)

Jenna Ladd | February 15, 2018

It has been accepted in many scientific communities that climate change can lead to civil unrest and violence, but a recent editorial in the Journal Nature tells readers not to be so sure.

The editorial’s authors did a literature review of 124 studies which assessed the link between climate change and war or civil unrest. They claim to have found three kinds of sampling biases among the studies. First, researchers overwhelmingly looked at regions where violence was already happening or had happened recently. Second, they noted that the studies primarily included countries in Africa and left out other nations that have been severely impacted by climate change. Finally, the mostly-white, Western researchers usually chose to study countries that were easily accessible to them and where the locals spoke English; think countries like Kenya.

Tobias Ide studies peace and war at the Georg Eckert Institute for International Textbook Research and is one of the paper’s authors. He said to The Atlantic, “If we only look at places where violence is, can we learn anything about peaceful adaptation to climate change? And if we only look at those places where there is violence, do we tend to see a link because we are only focusing on the places where there is violence in the first place?”

Solomon Hsiang has been openly critical of the paper’s claims. Hsiang’s 2013 findings showed that for every standard deviation change in precipitation or temperature, the likelihood that an area will experience civil unrest rises by 14 percent. The University of California Berkeley economist and public policy professor said in an email to The Atlantic, “Studying conflict-prone regions isn’t a problem, it’s what you would expect. Nobody is studying Ebola outbreaks by studying why Ebola is not breaking out in cafés in Sydney today, we study what happened in West Africa when there was an actual event.”

Either way, the paper draws attention to the myriad opportunities for study of climate change and conflict in countries outside of Africa and the Middle East. Ide said, “I was a bit surprised that even within American studies, there’s not really a focus on Latin America, basically. You can be concerned about Iraq, Syria, or India because of geopolitical relevance—but why not look for [climate-related conflict] in Mexico, or Honduras, or Brazil? Because that would have much sharper consequences for the United States.”

Crop production linked to regional changes in climate

Corn and soy plants can cool the climate on a regional level, but intensified conventional agriculture can harm water and soil quality. (Lana/flickr)

Jenna Ladd | February 14, 2018

A new study by researchers at Massachusetts Institute of Technology and Dartmouth College detail the way intensive agriculture has influenced precipitation and temperature patterns in the midwest.

During the second half of the 20th century, corn production in the midwest increased by 400 percent and soybean yields doubled due to more intensive agricultural practices. The study, which was published in Geophysical Research Letters, found that the midwest also saw significantly more precipitation and lower temperatures during the summer months over the same period of time. They concluded that the changes were not merely correlated, but that the land use change actually caused the regional climate changes.

The authors explain that each time plants take in carbon dioxide, they release moisture into the atmosphere through pore-like structures called stoma. With more plentiful and robust plants due to intensive agriculture, the amount of moisture corn and soy crops collectively release into the atmosphere has increased in the midwest since the 1950’s. This extra moisture, the study found, has caused summer air to cool and more precipitation to fall. In the last fifty years, average summertime rainfall in the midwest has increased by 15 percent and average summer temperatures have dropped by 0.5 degrees Celsius.

Roger Pielke Sr., a senior researcher at the University of Colorado at Boulder commented on the study, he said, “This is a really important, excellent study. The leadership of the climate science community has not yet accepted that human land management is at least as important on regional and local climate as the addition of carbon dioxide and other greenhouse gases into the atmosphere by human activities.”

Since completing the study, the researchers have developed a formula that accounts for the causative relationship between plants and regional climate changes that can be entered into U.S. regional climate models. It correctly predicted those changes that have been observed in the midwest over the last 50 years.

The study opens the door for further research into land use changes and how they can affect local climate.

November 2017 brought drought to Iowa

A portion of the dried up East Indian Creek southeast of Nevada during the 2012 drought. (Carl Wycoff/flickr)
Jenna Ladd | December 5, 2017

Last month was the driest month since 2007 according to state climatologist Harry Hillaker.

Hillaker spoke with Radio Iowa this week and said, “Overall a state average of .43 of an inch of moisture for the month, which is about 20 percent of what is usual. And actually the driest of any calendar month going back to November of 2007.”

Conditions were abnormally dry at all monitoring stations, especially in northwestern Iowa, where some areas of Ida county and Cherokee county received zero precipitation last month. The whole state only saw a minuscule amount of snow for the eighth time in Iowa’s 131-year weather record.  Hillaker said, “The statewide average was just a trace of snow and typically we’d get three to four inches of snow during the month of November.”

While there were some colder days in the beginning of November, warmer than average temperatures during the second half of the month made snowfall even less likely. The climatologist pointed out that there was virtually no precipitation in the state after the 18th of November.

November wraps up the fall season of September, October and November. Although November 2016 brought record-high temperatures, Iowa Environmental Mesonet reports that temperatures for last month were near average.

World Series game one was the hottest on record

Temperatures soared to 98 degrees Fahrenheit by the first pitch of Tuesday’s game. (accuweather)
Natalia Welzenbach-Marcu | October 26, 2017

The first game in the 2017 World Series, a match between the LA Dodgers and the Houston Astros, was held in California for the first time in 15 years—and brought with it a record-shattering 103 degrees. The previous World Series heat spike, 94 degrees, was recorded in 2001 in an Arizona game between the Arizona Diamondbacks and the New York Yankees. A heat warning for the area extended well into the game and finally lifted around 8pm—or about three hours after the game commenced.

The LA Dodgers, who won the game 3 to 1, might have owed something to the heat. High heat has been proven to have an effect on the distance a ball travels across the field. The University of Nevada-Reno’s Department of Math & Science put together a chart spanning analyzing the average number of home runs per game and the average distance of a batted ball, taking the temperatures of each game into account. After sifting through data from World Series games played between 2000-2011, they found that when the heat of a game spiked beyond 75 (the determined average temperature for an MLB game), home runs for any given team increased by an average of 2, while batted ball distance increased by roughly 2ft, suggesting that heat has a tangible effect on offensive play.

The heat spike spells bad news for other California residents, however, as the increased temperatures and accompanying 50 mph winds have made the ongoing wildfires in the Northern half of the state dangerously powerful. While the LA Dodgers beat the heat and made California proud, the state’s battle with wildfires will likely not ease up anytime soon.

Global temperatures continued to rise in September

A climate anomalies map from NOAA details significant some climate events during September 2017. (National Oceanic and Atmospheric Association)
Jenna Ladd | October 20, 2017

Earth’s climate continued to warm during September 2017, setting some alarming records.

September 2017 was the planet’s fourth warmest September since record-keeping began in 1880. The three warmest Septembers were in 2015, 2016 and 2014. This year’s September was especially notable because no El Niño effect was present. El Niño events typically bring warmer weather because they cause the ocean to release warm air into the atmosphere.

Even in the absence of an El Niño effect, temperatures in January through February of this year have made 2017 the second hottest year on the 138-year record kept by the National Oceanic and Atmospheric Administration (NOAA). In the top spot? 2016, which was 1.02 degrees Celsius above the 20th century average.

Sweltering temperatures were experienced across the globe. The hottest temperature in the Southern Hemisphere was 109 degrees Fahrenheit on September 27th in Birdsville, Australia. In the northern hemisphere, temperatures soared to 123 degrees Fahrenheit on September 3rd in Mitribah, Kuwait.

Record high temperatures are not without consequences. September 2017 also had the second lowest Antarctic sea ice cover during that month on record. The Arctic sea fared slightly better, coming in at number seven for record low sea ice cover during September.

A concise summery of NOAA and NASA’s September climate report can be found here.

On The Radio – Leaves drop early due to fall drought

Some leaves in Iowa fell to the ground before changing color this year due to drought. (Liz West/flickr)
Jenna Ladd | October 9, 2017

This week’s On The Radio segment discusses how drought conditions in late September pushed some trees into early dormancy.

Transcript: Tree leaves in Iowa began changing colors and falling to the ground earlier than usual this year due to drought conditions.

This is the Iowa Environmental Focus.

Leaf color change is closely tied to weather conditions. During the last week of September, the U.S. Drought Portal reported that about thirty percent of Iowa was experiencing abnormally dry conditions and about twenty-five percent of the state was in a moderate drought.

Officials from the Iowa Department of Natural Resources explained that if trees do not have enough moisture, they can be pushed into dormancy earlier than usual. As a result, many leaves died and fell from trees before they bursted into autumn’s hues of red, yellow and orange this year.

In a typical year, leaves change color in northern Iowa between the last week of September and the second week of October, from the first to third weeks of October in central Iowa and from the second to fourth weeks of October in southern Iowa.

For more information, visit iowa-environmental-focus-dot-org.

From the UI Center for Global and Regional Environmental Research, I’m Betsy Stone.