As temperatures rise and bobbers sink, it turns out anglers have a greater effect on fish populations than global warming, according to a new study led by the University of Wisconsin-Madison.
U.S. President Donald Trump speaks during the United Nations General Assembly at the United Nations headquarters on Sept. 23, 2025 in New York City. (Photo by Michael M. Santiago/Getty Images)
WASHINGTON — President Donald Trump harshly criticized fellow world leaders Tuesday at the United Nations General Assembly days after key allies of the United States recognized a Palestinian state, and as NATO vows to defend Europe amid recent Russian air incursions.
During his nearly hour-long address at the annual meeting in New York City, Trump briefly brushed on the Israel-Hamas war and his frustration with Russian President Vladimir Putin. But the U.S. president focused much of his attention on the “double-tailed monster” of immigration and energy that he said will cause Europe to “fail.”
“Your countries are going to hell,” Trump said, later adding: “And I’m really good at predicting things.”
“I’m telling you that if you don’t get away from the green energy scam, your country is going to fail. And if you don’t stop people that you’ve never seen before, that you have nothing in common with, your country is going to fail,” Trump continued.
Trump said the U.S. stands “ready to provide any country with abundant, affordable energy supplies if you need them, when most of you do,” and specifically encouraged the purchase of U.S. oil and gas.
The president attacked multilateral agreements to combat climate change, namely the Paris Climate Accord, and panned the overwhelmingly accepted science as “the greatest con job ever perpetrated on the world, in my opinion.”
Trump blames UN for faulty escalator, teleprompter
Trump attacked the U.N. as a body numerous times throughout his speech, including for what he claimed were a faulty escalator and teleprompter Tuesday.
“I don’t mind making this speech without a teleprompter, because the teleprompter is not working. I feel very happy to be up here with you nevertheless, and that way you speak more from the heart, I can only say that whoever’s operating this teleprompter is in big trouble,” Trump said at the top of his remarks.
Trump claimed he ended “seven wars” without the help of the U.N.
“All I got from the United Nations was an escalator that on the way up stopped right in the middle. If the first lady wasn’t in great shape, she would have fallen, but she’s in great shape. We’re both in good shape. We both stood,” he said. “And then a teleprompter that didn’t work. These are the two things I got from the United Nations, a bad escalator and a bad teleprompter. Thank you very much.”
U.N. General Assembly President Annalena Baerbock refuted Trump’s claim following his speech, saying, “As we are receiving queries, I would like to assure you that don’t worry, the U.N. teleprompters are working perfectly.”
Trump meets with Zelenskyy
Trump’s remarks came after negotiations to end Russia’s continued invasion into Ukraine have failed, despite Trump welcoming Putin to Alaska last month.
Trump met with Ukrainian President Volodymyr Zelenskyy for roughly an hour on the sidelines of the U.N. meeting Tuesday afternoon, where Trump said “we have great respect for the fight that Ukraine is putting up. It’s pretty amazing actually.”
Zelenskyy said he would brief the president on “good news” from the battlefield and said “we will continue until Russia will stop this war.”
Zelenskyy also highlighted conversations with European leaders regarding cutting off dependence on Russian oil and gas.
When asked by the press if he thinks NATO countries should shoot down Russian aircraft if they enter their airspace, Trump responded “Yes, I do,” according to journalists traveling with him.
Trump added it “depends on the circumstance” whether or not the U.S. would back up NATO allies.
When asked for an update on negotiations with Putin and if he still trusts the Russian president, Trump told reporters “I’ll let you know in about a month from now.”
Gaza crisis
The U.S. president’s speech to world leaders also comes after Israel all but blindsided the U.S. two weeks ago with a strike on Qatar, a key Middle East ally that hosts both a massive U.S. military presence as well as the Hamas political offices.
Trump received applause as he called for Hamas militants to release the remaining hostages kidnapped from Israel nearly two years ago during the group’s brutal attack. But he criticized any recognition of a Palestinian state as “a reward for these horrible atrocities.”
On Monday, France joined more than 150 countries to recognize Palestinian statehood. The United Kingdom, Canada, Australia and Portugal declared recognition Sunday.
Numerous world leaders, including those from Brazil, Indonesia, Turkey and Jordan, spoke on the assembly floor Tuesday about the humanitarian crisis in the Gaza Strip.
More than 65,000 people have been killed in Gaza since October 2023, according to Palestinian health authorities. The U.N. has declared a famine in the roughly 25-mile-long coastal strip that borders Israel, Egypt and the Mediterranean Sea.
“The terrorist attacks perpetrated by Hamas are indefensible from any angle, but nothing, absolutely nothing, justifies the ongoing genocide in Gaza,” Brazilian President Luiz Inácio Lula da Silva said before Trump took the floor.
“Under tons of rubble are buried tens of thousands of innocent women and children. There we can see that international humanitarian law and the myth of ethical exceptionalism of the West are also being buried there. This massacre would not have happened without the complicity of those who could have prevented it,” da Silva said.
Trump touts mass deportations
Administration officials seated at the U.S. table in the assembly hall included Trump’s Chief of Staff Susie Wiles, Secretary of State Marco Rubio, Secretary of Treasury Scott Bessent, Secretary of Energy Chris Wright, Middle East Special Envoy Steve Witkoff and recently confirmed U.N. Ambassador Mike Waltz, according to journalists traveling with the president.
Trump touted his domestic policies, including mass deportations and sending federal law enforcement and National Guard troops to Democratic-led American cities.
“Our message is very simple, if you come illegally into the United States, you’re going to jail, or you’re going back to where you came from, or perhaps even further than that. You know what that means,” Trump said.
He then thanked the El Salvadoran government for its “successful and professional job they’ve done in receiving and jailing so many criminals that entered our country.”
The U.S. agreed to pay El Salvador $4.76 million in March to detain up to 300 immigrant men, many of them Venezuelan nationals, for up to a year at a notorious mega-prison where several maintain they faced physical and psychological torture. Many argue they were wrongfully deported and are not affiliated with criminal gangs the administration has targeted.
Brazil, Venezuela
Trump also lauded his global tariff policy as his strategy to “defend our sovereignty and security throughout the world, including against nations that have taken advantage of former U.S. administrations for decades.”
He called out da Silva by name, saying he and the Brazilian leader quickly agreed before he walked on the floor to meet next week.
“I’m very sorry to say this, Brazil is doing poorly and will continue to do poorly. They can only do well when they’re working with us,” Trump said.
Trump imposed a 50% tariff on Brazilian goods coming into the U.S. after its Supreme Court prosecuted former Brazilian President Jair Bolsonaro for plotting a coup. Trump has dubbed the prosecution a “witch hunt.”
The U.S. Supreme Court will take up the question in November on whether Trump’s sweeping global tariffs are legal.
Trump also remarked on the U.S. military’s increased activity in the Caribbean Sea.
“Let’s put it this way, people don’t like taking big loads of drugs in boats anymore,” he said, referring to recent deadly U.S. strikeson boats near the coast of Venezuela.
The administration alleges the boats are involved in illegal drug smuggling. Trump’s use of deadly military force against the vessels has drawn both criticism and praise from U.S. lawmakers.
This story is from Floodlight, a nonprofit newsroom that investigates the powers stalling climate action. Sign up for Floodlight’s newsletter here.
In south-central Wisconsin, near-record warmth in January and two record-breaking summer heat waves have cross-country skiers nervous they won’t be getting much snow this winter — again.
And it’s not just skiers in Wisconsin who are worried. New research shows heat waves are prompting a growing number of Americans to make the connection between hotter weather and climate change.
Ski seasons in the United States have shrunk by an average of 5.5 to 7.1 days between 2000 and 2019 compared to the 1960s and ’70s, according to a 2024 study by researchers from Canada and Austria. And in the coming 25 years, ski seasons could be even shorter — by between two weeks and three months — depending on how much the world reduces its greenhouse gas emissions, the researchers said.
Tamara Bryant, executive director of a cross-country ski club in Madison, Wisconsin, has seen this dynamic firsthand — both in her professional and personal lives.
“I remember the winters where my son could build snow forts in the front yard, year after year, and we’re just not getting the same (amount of snow),” she said. “Having a white Christmas is not something we can totally rely on.”
Madison’s chain of lakes also aren’t freezing like they used to, creating hazards for people who fish on the ice.
Hilary Dugan, associate professor in the Center for Limnology at the University of Wisconsin-Madison, says back in the 1800s, lakes would remain frozen approximately 130 days a year, but now, on average, it’s about 75 days. Here, a young ice fisherman shows off his catch on Lake Monona in Madison in 2024. (Sharon Vanorny / Courtesy of Destination Madison)
Hilary Dugan, associate professor in the Center for Limnology at the University of Wisconsin-Madison, says back in the 1800s, lakes would remain frozen approximately 130 days a year, but now, on average, it’s maybe 75 days a year.
“That’s something that people around here notice because winter is a big part of life,” Dugan said. “Traditionally, winter would start in December (and) it would end probably like April. That meant that you could consistently go out and ice fish, cross-country ski, you know, winter recreation.
“We’re talking months of change — not just a couple of days.”
Heat curbs desert hiking
More than 1,700 miles away in Phoenix, dangerous heat has prompted officials to close the city’s extensive system of mountain trails. But that hasn’t stopped some from hiking in 100-degree-plus weather, leading to emergency rescues and the death of a 10-year-old last year.
The National Oceanic and Atmospheric Administration found 2024 was the hottest year in its 130-year climate record. NOAA reported the average annual temperature across the contiguous United States in 2024 was 55.5 degrees — or 3.5 degrees above the 20th-century average — heat that it said fueled a near-record number of tornadoes.
Hotter summers and warmer winters are not only disrupting outdoor activities. The record-breaking heat has also been driving national concern about climate change — more so even than dramatic events such as wildfires and hurricanes, according to new research.
Yale’s latest Climate Opinion Maps found that 65% of U.S. adults somewhat or strongly agree that global warming is affecting weather patterns, while 72% of adults nationally think global warming is real.
Its recent study showed that people’s interest in learning more about climate change consistently spikes during weather events like heat waves. And the public’s interest in climate change increases in specific areas experiencing extreme weather events, researchers found.
The Phoenix Mountains Preserve is criss-crossed with trails. But extreme heat caused by climate change is making hiking them much more dangerous. (Andy Hall / Floodlight)
“Certain weather events — like heat waves — seem to produce consistent jumps in climate change interest across all regions simultaneously,” the researchers wrote, “while others — like wildfires — show more geographic variation.”
The study involved research through Yale’s partnership with Google. The team analyzed online search trends across the country, finding that searches on climate change followed “consistent and predictable patterns.”
Heat waves in 2023 sparked consistent interest in climate change, the study found, while Hurricanes Helene and Milton in 2024 garnered an increase in searches only in the places affected by those storms. Similarly, interest in climate change increased during bouts of wildfires in the United States and Canada, but only in the areas most directly affected by the smoke, the study found.
The authors suggest the findings can be used by officials to help people prepare for extreme weather. And, the authors note, “this timing could help the public better understand the need to transition to renewable energy sources, reduce fossil fuels, update risk assessments, increase planning, and strengthen building codes.”
Heat not just inconvenient — it’s deadly
Climate Central’s analysis of heat streaks between 1970 and 2024 found that their frequency has at least doubled in nearly 200 cities across the Southwest, Northeast, Ohio River Valley and southeastern parts of the country — and those heat waves were attributed to greenhouse gas emissions.
The data, released in July by the nonprofit group of scientists and climate researchers, also found heat waves are the leading cause of weather-related deaths in the United States. In 2023, the group reported that 2,325 people in the United States died from extreme heat — a record high.
This heat, Phoenix Fire Department Capt. Rob McDade said, “It’s very dangerous.” In July 2024, a 10-year-old boy died from heat-related injuries while hiking South Mountain Park and Preserve with his family.
In 2021, Phoenix adopted a safety program to restrict access on parts of the city’s 200-plus miles of trails during extreme heat — especially on rugged stretches where it’s more difficult for the fire department to rescue hikers.
“We have more people hiking than ever, and we are seeing rescues that have to happen that definitely are related to the heat,” said Jarod Rogers, deputy director of the city’s Parks and Recreation Department.
Last year, between May 1 and Oct. 13, the city had 45 days of trail closures due to extreme heat. Since adopting the safety program, there have been fewer rescues — from 57 in 2021 down to 35 in 2024.
“The proof is in the pudding,” McDade said. “Setting up these restrictions is dramatically cutting back those extreme (heat) day mountain rescues.”
Warm weather hits winter sports
Rising temperatures are causing a different kind of risk in northern regions. Last winter, Dugan said she repeatedly heard about people being rescued after falling through melting lake ice.
“It felt higher than normal,” she said. “People are willing to go out on the thinnest ice to go get some fish. It’s definitely a passion for people here.”
Skiers are also feeling the burn from a warmer climate. Bryant, executive director for the MadNorSki Club (Madison Nordic Ski), said there has been little snow in recent years, shortening the cross-country skiing season.
Annual snowfall in Madison has decreased over the past three winters from 70 accumulated inches in 2022 to 43 inches in 2023 and 22 inches in 2024.
Bryant said popular ski races have had to cancel because of the lack of snowfall. Some event organizers have resorted to using artificially made snow.
The annual American Birkebeiner ski race in Cable, Wis., has had to adjust to less snow and warmer temperatures in recent years. In 2024, organizers used snowmaking machines to create a 10-kilometer loop instead of the normally linear 50- or 53-kilometer course. (Courtesy of American Birkebeiner Ski Foundation)
In 2017, organizers of the American Birkebeiner race (“Birkie”), which draws more than 10,000 nordic skiers to northern Wisconsin each year, canceled its cross-country ski races due to lack of snow.
In 2024, another low-snow year, Birkie organizers used snowmaking machines to create a 10-kilometer ski loop instead of the normally linear 50- or 53-kilometer course.
“In the photos, you would see this little white ribbon of snow on the trail, and it was brown everywhere else,” Bryant said, calling the recent lack of snow in Wisconsin “freaky.”
Birkie spokesman Shawn Connelly said the American Birkebeiner Ski Foundation has kept its ski events running thanks to donor funding to purchase the snow-making equipment. “As long as we have the cold, we’ll have the snow,” Connelly vowed, “and we’ll continue to host North America’s largest annual cross-country ski race.”
Trump seeks to halt U.S. climate push
While the Yale study shows Americans are increasingly concerned about climate change, President Donald Trump’s administration is moving in the opposite direction.
In July, the U.S. Environmental Protection Agency proposed rescinding the 2009 Endangerment Finding, which scientifically characterized planet-warming greenhouse gases as a danger to human health and the environment. The ruling was used as the foundation for the federal government’s regulation of emissions from vehicles and power plants for the last 16 years.
The proposal comes after the Trump administration gutted many of the initiatives of former President Joe Biden’s Inflation Reduction Act that aimed to reduce the country’s climate impact over the next two decades.
Environmental advocates have accused the Trump administration of “burying its head in sand” when it comes to the climate crisis.
“Americans are already suffering from stronger hurricanes, more severe heat waves and floods, and more frequent fires,” Fred Krupp, president of the Environmental Defense Fund, said in a prepared statement. “(Americans) are watching these climate disasters get worse (and) the danger to their lives and health intensify.”
Floodlight is a nonprofit newsroom that investigates the powers stalling climate action.
Four New Nuclear Reactors and Forever Radioactive Waste in Calhoun County, Texas First Intervention Against SMRs in the U.S. LONG MOTT, Texas – This week, San Antonio Bay Estuarine Waterkeeper (Waterkeeper) intervened to stop four proposed experimental nuclear power reactors targeted for Long Mott, Texas – a community in coastal Calhoun County – the first …
Jessika Trancik, a professor in MIT’s Institute for Data, Systems, and Society, has been named the new director of the Sociotechnical Systems Research Center (SSRC), effective July 1. The SSRC convenes and supports researchers focused on problems and solutions at the intersection of technology and its societal impacts.
Trancik conducts research on technology innovation and energy systems. At the Trancik Lab, she and her team develop methods drawing on engineering knowledge, data science, and policy analysis. Their work examines the pace and drivers of technological change, helping identify where innovation is occurring most rapidly, how emerging technologies stack up against existing systems, and which performance thresholds matter most for real-world impact. Her models have been used to inform government innovation policy and have been applied across a wide range of industries.
“Professor Trancik’s deep expertise in the societal implications of technology, and her commitment to developing impactful solutions across industries, make her an excellent fit to lead SSRC,” says Maria C. Yang, interim dean of engineering and William E. Leonhard (1940) Professor of Mechanical Engineering.
Much of Trancik’s research focuses on the domain of energy systems, and establishing methods for energy technology evaluation, including of their costs, performance, and environmental impacts. She covers a wide range of energy services — including electricity, transportation, heating, and industrial processes. Her research has applications in solar and wind energy, energy storage, low-carbon fuels, electric vehicles, and nuclear fission. Trancik is also known for her research on extreme events in renewable energy availability.
A prolific researcher, Trancik has helped measure progress and inform the development of solar photovoltaics, batteries, electric vehicle charging infrastructure, and other low-carbon technologies — and anticipate future trends. One of her widely cited contributions includes quantifying learning rates and identifying where targeted investments can most effectively accelerate innovation. These tools have been used by U.S. federal agencies, international organizations, and the private sector to shape energy R&D portfolios, climate policy, and infrastructure planning.
Trancik is committed to engaging and informing the public on energy consumption. She and her team developed the app carboncounter.com, which helps users choose cars with low costs and low environmental impacts.
As an educator, Trancik teaches courses for students across MIT’s five schools and the MIT Schwarzman College of Computing.
“The question guiding my teaching and research is how do we solve big societal challenges with technology, and how can we be more deliberate in developing and supporting technologies to get us there?” Trancik said in an article about course IDS.521/IDS.065 (Energy Systems for Climate Change Mitigation).
Trancik received her undergraduate degree in materials science and engineering from Cornell University. As a Rhodes Scholar, she completed her PhD in materials science at the University of Oxford. She subsequently worked for the United Nations in Geneva, Switzerland, and the Earth Institute at Columbia University. After serving as an Omidyar Research Fellow at the Santa Fe Institute, she joined MIT in 2010 as a faculty member.
Trancik succeeds Fotini Christia, the Ford International Professor of Social Sciences in the Department of Political Science and director of IDSS, who previously served as director of SSRC.
Professor Jessika Trancik conducts research on technology innovation and energy systems.
(WASHINGTON, DC) — Today, it was reported that the Trump administration is preparing to cancel $7 billion in federal solar grants intended to help low- and moderate-income families access rooftop and community solar. The decision would eliminate the Solar for All program, a cornerstone of recent federal efforts to lower energy costs and expand access to clean …
There has been broad agreement about the greenhouse effect for over a century.
In 1824, Joseph Fourier calculated that Earth ought to be much colder given its distance from the sun, and theorized that the atmosphere acts as a blanket, trapping heat and keeping the planet warmer than it would be otherwise.
Scientists later hypothesized that higher concentrations of greenhouse gases could raise temperatures. In 1896, Svante Arrhenius attempted to quantify this; his predictions remain on the high end of current climate models.
The basic science of the greenhouse effect is fairly simple: certain atmospheric gases such as carbon dioxide trap and redirect outgoing heat; some is radiated back downward, causing heat build up and temperatures to rise.
In 2021, the IPCC concluded it is unequivocal that human emission of greenhouse gases are the primary cause of modern warming.
A few years ago, Holly Jones started studying the micro-climate and the topography on her family farm in Crawfordsville, Iowa, about 40 miles south of Iowa City. Jones said learning more about the landscape of her fifth generation flower farm helped her recognize some of the ways weather and climate change could affect her operation.
“There are some areas of our land that are a little higher than others,” Jones said. “That’s going to impact, for example, when we’re looking out for frost advisories or frost concerns really early in the season or the end.”
Around this time, the U.S. Department of Agriculture updated its plant hardiness zones map, which divides the United States into 13 zones based on average annual minimum temperatures in a given time period.
Todd Einhorn, an associate professor in the Department of Horticulture at Michigan State University, said simply put plant hardiness zones help gardeners and farmers determine which plants are most likely to survive winters in a specific location.
Jones’ farm, called Evergreen Hill, is currently in zone 5b. The USDA found that for her area the temperature had increased by 1 degree Fahrenheit between 2012 and 2023 – a trend experts say will continue in the Upper Midwest.
In response to the changing climate and her deeper understanding of her land, Jones created “crossover plans” for the farm, planting flower varieties with overlapping bloom times. If one species is late to flower or runs its course early, she has other plants that can fill in as the farm’s “focal flower” at any given time.
Jones works to be transparent with customers about whether they can have certain flowers by a specific date when she takes orders.
She said she and her team have learned that they must be flexible when it comes to farming in a changing climate since she does not have control over growing conditions.
“We can prepare as much as we want, but there’s so much variability now in growing, especially in the ways that we grow that you just have to be prepared to pivot and adapt,” Jones said.
Jones won’t be the only one adapting.
Plant hardiness zones are shifting northward nationwide as the country continues to warm, affecting farmers, gardeners and producers across the country. The biggest changes in the coming decades are predicted to be in the Upper Midwest. The Midwest produces 27% of the nation’s agricultural goods.
What are plant hardiness zones?
The USDA Plant Hardiness Zone map has 13 zones, which serve as guidelines for growers on what kind of plants will grow well in their area.
“Hardiness zones are meant to at least delineate which species or cultivars of species could be planted based on their survival,” said Einhorn, who specializes in plant hardiness science, particularly with fruit tree species.
Each zone covers about 10 degrees — for example, Iowa lies primarily in zone 5, which means its coldest temperatures range from -20 degrees to -10 degrees Fahrenheit on average. Each zone is further divided into 5 degree half zones — the northern half of Iowa is in 5a, the southern half in 5b.
Madelynn Wuestenberg, an agricultural climatology extension specialist with Iowa State University, said that plant hardiness zones are defined by their average coldest temperatures. The averages are calculated over 30 years.
In 2023, using new averages, the USDA updated the map, moving about half of the country up by half a plant zone, meaning average minimum temperatures rose by zero to 5 degrees in the affected places.
Why are the zones shifting north?
Climate Central, a nonprofit researching climate change and how it affects people, analyzed 243 locations around the United States and found that about 67% of the locations studied based on National Oceanic and Atmospheric Administration data have already shifted to warmer planting zones from the mid-1900s to present.
The researchers found that the Northwest and the Southwest, along with Alaska, have been the most affected to date.
With unabated climate change about 90% of locations examined will likely shift to warmer planting zones by the middle of this century. The Upper Midwest is predicted to be affected most.
Wuestenberg said winter temperatures in the Midwest are becoming warmer on average, compared to decades past.
“What we saw from the 1981 to 2010 climatology versus the 1991 to 2020 climatology is we’re really starting to see warming across the U.S.,” Wuestenberg said. “And this has been observed for a long time, and really it’s a pretty consistent overall warming, but the specific amount of warming varies region to region across the U.S.”
Of the cities with the highest predicted temperature change between now and mid-century, a majority of the top 25 are in the Mississippi River Basin.
Madison, Wisconsin, for example, is projected to switch from zone 5b to 6a as the average coldest temperature is expected to increase by 8.4 degrees Fahrenheit.
Using data from the National Oceanic and Atmospheric Administration, Climate Central analyzed how rising temperatures might change growing conditions around the country. It found that if climate change continues unabated, 90% of the studied cities will shift to warmer planting zones by mid-century, including Madison, Wis. (Climate Central)
Jefferson City, Missouri, will likely change from zone 6b to zone 7b as the area’s average cold temperatures are projected to increase by 8.3 degrees Fahrenheit.
In Dubuque, Iowa, the average coldest temperatures are expected to rise by 8.3 degrees Fahrenheit, and producers will go from zone 5a to 6a.
Average cold temperatures in Cedar Rapids, Iowa, are on course to warm by 8.2 degrees Fahrenheit, and the region is expected to jump an entire planting zone to 6a.
The shift in plant hardiness zones could force some growers across the country to select plants that are adapted to a wider and warmer range of temperatures to survive warmer winters and earlier frosts and thaws.
In some cases, that could mean new opportunities.
Dean Colony runs Colony Acres Family Farm in North Liberty, Iowa. On his 200-acre farm, he grows pumpkins, corn, soybeans and zinnias.
His farm is currently in plant hardiness zone five, but Colony said it could be a matter of time before Iowa is able to produce peaches like Missouri and Kentucky can.
“How many more years is it going to be? I mean, we could grow peaches in Iowa, but it seems like they grow them way better down there,” Colony said. “So is it a matter of time before that comes here?”
Wuestenberg said one challenge with the shifting zones is that they are based on climatological averages and do not take atypical and significant frost or freeze events into account, which can be challenging for producers.
Who will be most affected?
Wuestenberg said gardeners and fruit tree producers will likely be more concerned about the shifting zones, rather than row crop producers.
Fruit trees and vines need a certain number of chilling hours, which is the minimum period of cold weather a fruit tree needs to blossom.
For example, Einhorn said most apple trees require about a thousand chilling hours in the winter to break their dormancy period and bloom in the spring.
But with winters warming, even by a few degrees, apple trees will want to break dormancy earlier.
“Instead of being at 30 degrees Fahrenheit in the winter, maybe now the days are at 34 (degrees Fahrenheit) and that little bit of warming actually has a humongous effect on a tree,” Einhorn said.
The apple trees could start flowering in late February or early March.
“Unfortunately, what can happen is overall, winter may have been warmer, but we still might get a March, April frost. And once that happens, those buds, those flowers, are exposed to that cold temperature, and then it kills them,” Wuestenberg said.
This could lead to reduced fruit yields later in the season.
But Einhorn said there are ways that producers can work within the unpredictable conditions.
For example, there are various methods for raising temperatures for trees during a freeze, including using fans to pull warm air out of the atmosphere and running water over plants. There are also research efforts underway breeding new plants that have either delayed blooms or can withstand the new conditions.
Meanwhile, farmers will continue to adapt. Jones, the flower farmer, has noticed strong winds and storms coming through the eastern Iowa region. She’s planted sunflowers in windier areas of the farm because they can withstand stronger gusts. More delicate flowers go near trees for natural protection. She also uses netting to help stabilize flowers from winds, rains and storms.
“At the end of the season, we’re at the mercy of our climate and the weather,” Jones said. “And that can greatly impact what we have in any given season.”
New Poll: American Voters Support Federal Investments in Electric Vehicles Broad, Bipartisan Support for EV Investments and Incentives that Lower Costs, Expand Access, and Help the U.S. Beat China in the Race for Auto Manufacturing WASHINGTON, D.C. – A new bipartisan national poll conducted by Meeting Street Insights and Hart Research finds broad public support …
As a major contributor to global carbon dioxide (CO2) emissions, the transportation sector has immense potential to advance decarbonization. However, a zero-emissions global supply chain requires re-imagining reliance on a heavy-duty trucking industry that emits 810,000 tons of CO2, or 6 percent of the United States’ greenhouse gas emissions, and consumes 29 billion gallons of diesel annually in the U.S. alone.
A new study by MIT researchers, presented at the recent American Society of Mechanical Engineers 2024 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference, quantifies the impact of a zero-emission truck’s design range on its energy storage requirements and operational revenue. The multivariable model outlined in the paper allows fleet owners and operators to better understand the design choices that impact the economic feasibility of battery-electric and hydrogen fuel cell heavy-duty trucks for commercial application, equipping stakeholders to make informed fleet transition decisions.
“The whole issue [of decarbonizing trucking] is like a very big, messy pie. One of the things we can do, from an academic standpoint, is quantify some of those pieces of pie with modeling, based on information and experience we’ve learned from industry stakeholders,” says ZhiYi Liang, PhD student on the renewable hydrogen team at the MIT K. Lisa Yang Global Engineering and Research Center (GEAR) and lead author of the study. Co-authored by Bryony DuPont, visiting scholar at GEAR, and Amos Winter, the Germeshausen Professor in the MIT Department of Mechanical Engineering, the paper elucidates operational and socioeconomic factors that need to be considered in efforts to decarbonize heavy-duty vehicles (HDVs).
Operational and infrastructure challenges
The team’s model shows that a technical challenge lies in the amount of energy that needs to be stored on the truck to meet the range and towing performance needs of commercial trucking applications. Due to the high energy density and low cost of diesel, existing diesel drivetrains remain more competitive than alternative lithium battery-electric vehicle (Li-BEV) and hydrogen fuel-cell-electric vehicle (H2 FCEV) drivetrains. Although Li-BEV drivetrains have the highest energy efficiency of all three, they are limited to short-to-medium range routes (under 500 miles) with low freight capacity, due to the weight and volume of the onboard energy storage needed. In addition, the authors note that existing electric grid infrastructure will need significant upgrades to support large-scale deployment of Li-BEV HDVs.
While the hydrogen-powered drivetrain has a significant weight advantage that enables higher cargo capacity and routes over 750 miles, the current state of hydrogen fuel networks limits economic viability, especially once operational cost and projected revenue are taken into account. Deployment will most likely require government intervention in the form of incentives and subsidies to reduce the price of hydrogen by more than half, as well as continued investment by corporations to ensure a stable supply. Also, as H2-FCEVs are still a relatively new technology, the ongoing design of conformal onboard hydrogen storage systems — one of which is the subject of Liang’s PhD — is crucial to successful adoption into the HDV market.
The current efficiency of diesel systems is a result of technological developments and manufacturing processes established over many decades, a precedent that suggests similar strides can be made with alternative drivetrains. However, interactions with fleet owners, automotive manufacturers, and refueling network providers reveal another major hurdle in the way that each “slice of the pie” is interrelated — issues must be addressed simultaneously because of how they affect each other, from renewable fuel infrastructure to technological readiness and capital cost of new fleets, among other considerations. And first steps into an uncertain future, where no one sector is fully in control of potential outcomes, is inherently risky.
“Besides infrastructure limitations, we only have prototypes [of alternative HDVs] for fleet operator use, so the cost of procuring them is high, which means there isn’t demand for automakers to build manufacturing lines up to a scale that would make them economical to produce,” says Liang, describing just one step of a vicious cycle that is difficult to disrupt, especially for industry stakeholders trying to be competitive in a free market.
Quantifying a path to feasibility
“Folks in the industry know that some kind of energy transition needs to happen, but they may not necessarily know for certain what the most viable path forward is,” says Liang. Although there is no singular avenue to zero emissions, the new model provides a way to further quantify and assess at least one slice of pie to aid decision-making.
Other MIT-led efforts aimed at helping industry stakeholders navigate decarbonization include an interactive mapping tool developed by Danika MacDonell, Impact Fellow at the MIT Climate and Sustainability Consortium (MCSC); alongside Florian Allroggen, executive director of MITs Zero Impact Aviation Alliance; and undergraduate researchers Micah Borrero, Helena De Figueiredo Valente, and Brooke Bao. The MCSC’s Geospatial Decision Support Tool supports strategic decision-making for fleet operators by allowing them to visualize regional freight flow densities, costs, emissions, planned and available infrastructure, and relevant regulations and incentives by region.
While current limitations reveal the need for joint problem-solving across sectors, the authors believe that stakeholders are motivated and ready to tackle climate problems together. Once-competing businesses already appear to be embracing a culture shift toward collaboration, with the recent agreement between General Motors and Hyundai to explore “future collaboration across key strategic areas,” including clean energy.
Liang believes that transitioning the transportation sector to zero emissions is just one part of an “energy revolution” that will require all sectors to work together, because “everything is connected. In order for the whole thing to make sense, we need to consider ourselves part of that pie, and the entire system needs to change,” says Liang. “You can’t make a revolution succeed by yourself.”
The authors acknowledge the MIT Climate and Sustainability Consortium for connecting them with industry members in the HDV ecosystem; and the MIT K. Lisa Yang Global Engineering and Research Center and MIT Morningside Academy for Design for financial support.
A new study by MIT researchers quantifies the impact of a zero-emission truck’s design range on its energy storage requirements and operational revenue.
A new study on behalf of Milliken has identified the top U.S. states for sustainable energy production. The rapid rise of the sustainable energy sector worldwide has been one of the most important technological and economic stories of recent years. Continued urgency to mitigate the impact of climate change has spurred governments and companies to speed the transition …
Climate anxiety affects nearly half of young people aged 16-25. Students like second-year Rachel Mohammed find hope and inspiration through her involvement in innovative climate solutions, working alongside peers who share her determination. “I’ve met so many people at MIT who are dedicated to finding climate solutions in ways that I had never imagined, dreamed of, or heard of. That is what keeps me going, and I’m doing my part,” she says.
Hydrogen-fueled engines
Hydrogen offers the potential for zero or near-zero emissions, with the ability to reduce greenhouse gases and pollution by 29 percent. However, the hydrogen industry faces many challenges related to storage solutions and costs.
Mohammed leads the hydrogen team on MIT’s Electric Vehicle Team (EVT), which is dedicated to harnessing hydrogen power to build a cleaner, more sustainable future. EVT is one of several student-led build teams at the Edgerton Center focused on innovative climate solutions. Since its founding in 1992, the Edgerton Center has been a hub for MIT students to bring their ideas to life.
Hydrogen is mostly used in large vehicles like trucks and planes because it requires a lot of storage space. EVT is building their second iteration of a motorcycle based on what Mohammed calls a “goofy hypothesis” that you can use hydrogen to power a small vehicle. The team employs a hydrogen fuel cell system, which generates electricity by combining hydrogen with oxygen. However, the technology faces challenges, particularly in storage, which EVT is tackling with innovative designs for smaller vehicles.
Presenting at the 2024 World Hydrogen Summit reaffirmed Mohammed’s confidence in this project. “I often encounter skepticism, with people saying it’s not practical. Seeing others actively working on similar initiatives made me realize that we can do it too,” Mohammed says.
The team’s first successful track test last October allowed them to evaluate the real-world performance of their hydrogen-powered motorcycle, marking a crucial step in proving the feasibility and efficiency of their design.
MIT’s Sustainable Engine Team (SET), founded by junior Charles Yong, uses the combustion method to generate energy with hydrogen. This is a promising technology route for high-power-density applications, like aviation, but Yong believes it hasn’t received enough attention. Yong explains, “In the hydrogen power industry, startups choose fuel cell routes instead of combustion because gas turbine industry giants are 50 years ahead. However, these giants are moving very slowly toward hydrogen due to its not-yet-fully-developed infrastructure. Working under the Edgerton Center allows us to take risks and explore advanced tech directions to demonstrate that hydrogen combustion can be readily available.”
Both EVT and SET are publishing their research and providing detailed instructions for anyone interested in replicating their results.
The team’s single-occupancy car Nimbus won the American Solar Challenge two years in a row. This year, the team pushed boundaries further with Gemini, a multiple-occupancy vehicle that challenges conventional perceptions of solar-powered cars.
Senior Andre Greene explains, “the challenge comes from minimizing how much energy you waste because you work with such little energy. It’s like the equivalent power of a toaster.”
Gemini looks more like a regular car and less like a “spaceship,” as NBC’s 1st Look affectionately called Nimbus. “It more resembles what a fully solar-powered car could look like versus the single-seaters. You don’t see a lot of single-seater cars on the market, so it’s opening people’s minds,” says rising junior Tessa Uviedo, team captain.
All-electric since 2013
The MIT Motorsports team switched to an all-electric powertrain in 2013. Captain Eric Zhou takes inspiration from China, the world’s largest market for electric vehicles. “In China, there is a large government push towards electric, but there are also five or six big companies almost as large as Tesla size, building out these electric vehicles. The competition drives the majority of vehicles in China to become electric.”
The team is also switching to four-wheel drive and regenerative braking next year, which reduces the amount of energy needed to run. “This is more efficient and better for power consumption because the torque from the motors is applied straight to the tires. It’s more efficient than having a rear motor that must transfer torque to both rear tires. Also, you’re taking advantage of all four tires in terms of producing grip, while you can only rely on the back tires in a rear-wheel-drive car,” Zhou says.
Zhou adds that Motorsports wants to help prepare students for the electric vehicle industry. “A large majority of upperclassmen on the team have worked, or are working, at Tesla or Rivian.”
Former Motorsports powertrain lead Levi Gershon ’23, SM ’24 recently founded CRABI Robotics — a fully autonomous marine robotic system designed to conduct in-transit cleaning of marine vessels by removing biofouling, increasing vessels’ fuel efficiency.
“The environmental impact is always something that we consider when we’re making design decisions and operational decisions. We’ve thought about things like biodegradable composites and parachutes,” says rising junior Hailey Polson, team captain. “Aerospace has been a very wasteful industry in the past. There are huge leaps and bounds being made with forward progress in regard to reusable rockets, which is definitely lowering the environmental impact.”
Collecting climate change data with autonomous boats
Arcturus, the recent first-place winner in design at the 16th Annual RoboBoat Competition, is developing autonomous surface vehicles that can greatly aid in marine research. “The ocean is one of our greatest resources to combat climate change; thus, the accessibility of data will help scientists understand climate patterns and predict future trends. This can help people learn how to prepare for potential disasters and how to reduce each of our carbon footprints,” says Arcturus captain and rising junior Amy Shi.
“We are hoping to expand our outreach efforts to incorporate more sustainability-related programs. This can include more interactions with local students to introduce them to how engineering can make a positive impact in the climate space or other similar programs,” Shi says.
Shi emphasizes that hope is a crucial force in the battle against climate change. “There are great steps being taken every day to combat this seemingly impending doom we call the climate crisis. It’s important to not give up hope, because this hope is what’s driving the leaps and bounds of innovation happening in the climate community. The mainstream media mostly reports on the negatives, but the truth is there is a lot of positive climate news every day. Being more intentional about where you seek your climate news can really help subside this feeling of doom about our planet.”
Electric Vehicle Team members (from left to right) Anand John, Rachel Mohammed, and Aditya Mehrotra '22, SM '24 monitor their bike’s performance, battery levels, and hydrogen tank levels to estimate the vehicle’s range.
Current methods used to process hydrogen into a usable fuel are cost-prohibitive, but several new innovations are promising to open the door to cost-competitive green hydrogen. Hydrogen is well positioned to be the fuel of the future. However, a commercially viable transition to green hydrogen – the environmentally friendly version of the fuel – seems …