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Better catch up, Dad, my daughter said as she and her brother skated into the night. We were at the start of the Rideau Canal Skateway, part of a United Nations World Heritage Site cutting through the heart of the Canadian capital. At 7.8 kilometers, or roughly 5 miles from end to end, the skateway is the worlds largest ice rink and one whose very existence is threatened by climate change. But on our recent visit, as the wind chill dropped to 3 degrees Fahrenheit, the ice was cold and fast. More than 1 million people skated on the Rideau Canal Skateway in Ottawa, Ontario, this winter. [Photo: Phil McKenna/Inside Climate News] The free public rink has attracted millions of tourists since the city began maintaining it as a skateway in 1971. In the early years, visitors could typically count on a skating season that lasted from late December through February or early March. Recently, however, the season has been shrinking. Two years ago, in the winter of 2022-23, the skateway didnt open at all. This year, ice on the canal bounced back, with one of its longest seasons in recent memory. The cold that weve had, its fantastic, said Bruce Devine, the senior manager for facilities and programs for Canadas National Capital Commission, which oversees the skateway. Were back to where we were three years ago. This years season, which hosted more than 1.1 million skaters from January 11 until it officially closed on March 10, may be an anomaly. Winters in the Ottawa region will be five weeks shorter by 2050 if global greenhouse gas emissions continue unabated, according to a report the NCC and the City of Ottawa commissioned in 2020. Perhaps even worse for the skateway: There would be 35% fewer very cold days, days below minus 10 degrees Celsius (14 degrees Fahrenheit). Water, of course, freezes at 32 degrees Fahrenheit, but intense cold of 14 degrees or below is needed for significant ice formation. In 2022, the NCC launched a four-year study of the canal and its ice with researchers from Carleton University in Ottawa. Their aim is to figure out how to keep the skateway open and thriving as winters become more unpredictable. Much of the research focuses on getting a baseline understanding of the ice and how it varies across the canal. Researchers use ice augers to drill into it, measure its thickness and collect core samples to assess its quality. They also employ ground penetrating radar that they pull across the ice on a sled, a weather station that sits on top of the ice and sensors that are either suspended in the water column or embedded into the ice to collect a wealth of data on conditions across the skateway. Were then able to . . . use that information to model the predictions of ice growth based on current weather patterns or historical weather patterns, said Shawn Kenny, a professor in the Department of Civil and Environmental Engineering at Carleton University. The researchers are also looking at how they can create ideal conditions for ice to grow, especially early in the season when the days are shorter and the sun is lower on the horizon. Slush canons, similar to the snow cannons used by ski resorts, can help in the early stages of ice formation. The canons spray semi-frozen water onto the canal to help crystallize a thick layer of ice on the surface. Once an initial ice layer has formed, NCC staff use pumps to draw water from beneath the ice and discharge it on the surface. Though not a new approach, the technique speeds ice formation by exposing the water directly to cold air rather than through a layer of ice, which acts as insulation against the cold. Kenny and colleagues are also testing snow bots, lightweight, 3D-printed semiautonomous robots that can clear snow from the canal when the ice is still too thin for heavier snow-removal equipment to operate safely. If left uncleared, the snow that accumulates on the ice can further insulate the water beneath the ice and inhibit its growth. The 2022-23 season, when the canal failed to open, had 160% more snow than the average winter. All that additional snow impeded ice formation, Kenny said. Still, efforts the researchers are employing to enhance ice formation have their limits. If its warm, you wont grow ice, Kenny said. A Provocative Idea for Rideau Canals Ice In April 2023, on the heels of the first winter in more than half a century that the skateway failed to open, a Canadian refrigeration expert floated a provocative idea. Why not use heat pumps to pull heat from the waters of the Rideau Canal and push it into surrounding buildings, creating a thermal network that would simultaneously cool the skateway while heating surrounding homes or federal office buildings? The idea was pitched in a blog post by Wayne Borrowman, the director of research and development for CIMCO Refrigeration, a Canadian company that claims tohave built more than half of the worlds ice rinks. Typically, indoor ice rinks vent large volumes of waste heat in the form of steam as they circulate refrigerants to draw heat out of the concrete pads beneath the ice. Some 20 years ago, CIMCO started installing new refrigeration systems that use heat pumpsa system of heat exchangers, pumps, and compressorsto harvest the waste heat. The company then used it to provide space heating to locker rooms, concession areas, and other parts of the building. In 2019, the company deployed the concept at an outdoor ice rink in North Vancouver. Waste heat captured from the rink heats nearby buildings, the equivalent of 43 homes in all. The nearly 5-mile-long Rideau Canal Skateway cuts through the heart of Ottawa and is part of a United Nations World Heritage Site. [Photo: Phil McKenna/Inside Climate News] Borrowman estimated the Rideau Canal Skateway is about the size of 60 ice rinks. The canal could serve as a heat source for thousands of homes without the need to burn fossil fuels and would help cool the skateway as an added benefit, he said. A project of such scale may sound crazy to some, but Ive spent my whole career involved with the design and installation of large cooling systems and I can assure you from an engineering perspective it is possible, he wrote in 2023. Neither CIMCO nor Borrowman have gone further with the proposal, something he recently described as a thought experiment driven in part by national pride. This is something that in our Canadian capital is a world-class event, he said. Where else can you skate down a canal right in the middle of a city in wintertime? Ice skating on canals was once a national pastime in the Netherlands, but in a warming world such activities are now largely a thing of the past. Elfstedentocht, a winter skating tour and race across the northern province of Friesland that used to draw thousands of participants hasnt happened since 1997 due to a lack of ice. Kenny, of Carleton University, said the thermal network Borrowman proposed is theoretically possible. But the cost for such a system, including the installation of hundreds of miles of refrigeration pipes running along the bottom and potentially sides of the canal, would likely be prohibitively expensive. Similar cost concerns were raised about the skateway itself for more than half a century before its opening in 1971. Kenny also noted that the canal is popular for boating in the summertime, something that could make any refrigeration pipes along the bottom of the canal prone to damage from anchor strikes. Another option may be a more limited application of heat pumps for the most difficult to freeze sections of the skateway. Stormwater pipes that empty into the northernmost portion of the Rideau Canal dump water that is up to 50 degrees Fahrenheit, or about 10 degrees warmer than the winter temperature of water in the canal. NCC has added pipes to divert the stormwater discharge further from the start of the skateway in recent years, but the area remains one of the last sections of the canal to freeze. You could install mechanical equipment such as plate and frame heat exchangers and use heat pumps to bring down that temperature so that at least you dont have that issue of preventing the ice formation of that specific region, said Connor Dacquay, president of EcoFease, a company based in Canada that distributes software for managing thermal energy networks. Dacquay said such a system would be similar to the False Creek Neighbourhood Energy Utility in Vancouver that uses waste heat captured from sewage to provide space heating and hot water to nearby buildings. Dacquay said the system could potentially tie into an existing district energy system already operating in downtown Ottawa, which provides heating and cooling to federal buildings including Canadas Parliament and Supreme Court. The system could also run in reverse in the summertime, drawing heat out of buildings to cool them, while discharging the waste heat into the canal, Dacquay said. Cole Van De Ven, an assistant professor in environmental engineering at Carleton University, said the intermittent flow rate of the stormwater runoff into the canal could make such a heat recovery system challenging from a financial standpoint. Federal and municipal permitting issues could also pose a challenge, Van De Ven said. Installing rain gardens that slow down and reduce stormwater runoff may be a less costly solution. Such an approach would have an added benefit of removing salt, which also impedes ice formation, from the stormwater, Van De Ven added. Skating Through Ottawa Visiting Ottawa during a late February cold snap, the thought of anything being too warm was hard to imagine. Despite redundant layers of insulation, including snow pants, jackets, hats, gloves, neck warmers, and thermal underwear, we still couldnt keep out the cld. Initially, the frigid temperatures were manageable as a healthy tailwind and our own adrenaline propelled us south along the skateway. We glided beneath bridges, around bends, and past rest stops as kilometer markers on the side of the canal seemed to fly by. The canal itself, the entirety of which stretches 125 miles from Ottawa to Kingston, Ontario, opened in 1832 to provide an alternative trade route for ships in what was then the British colony of Upper Canada. Prior to the canals opening, British ships used the St. Lawrence River, which bordered New York state and was vulnerable to attack. Now, as U.S. President Donald Trump prepared to place tariffs on Canadian imports and mused about Canada becoming the 51st state, Canadians were again considering alternative trade routesin the form of new oil and gas pipelines that would bypass the United States but would also fuel further warming. Food vendors, skate rental shops, and changing rooms are stationed along the canal. [Photo: Phil McKenna/Inside Climate News] Nearing the halfway point of the skateway, we stopped at a food truck parked on the ice. It sold a mix of Asian street food and poutine, a Canadian staple of French fries and melted cheese slathered in gravy. We ate quickly inside a heated changing room, determined to continue on our way. But by the time we got back outside, our bodies had cooled. To be totally honest, my feet are getting kind of cold, my son said, voicing what each of us knew to be true but didnt want to admit. It was time to turn around and head back to our hotel, content to know that at least for now, on a canal in Ottawa, winter persists. By Phil McKenna, Inside Climate News This article originally appeared on Inside Climate News. It is republished with permission. Sign up for its newsletter here.
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The Trump administration has repeatedly said it wants to deport as many people as possible. What that means for the estimated 8.3 million unauthorized immigrants in the American workforce is unclear. It is also unclear whether those mass deportations will happen. The deportations recorded so far arent on track to meet Trumps goal. And the economic reality is that deporting huge numbers of immigrants could cause severe labor shortages. As many as 1 in 20 U.S. workers are unauthorized immigrants. If they all were forced to leave or were too scared to show up to work, it could harm the economy. In some cases, the labor rights of unauthorized workers could be another obstacle. I am a professor who has spent more than two decades researching immigrant labor organizing. In Scaling Migrant Worker Rights, a book I coauthored with sociologist Shannon Gleeson, we explained that unauthorized workers in the U.S. have labor rights and how those workers can defend them. While challenging, in some cases, labor laws have protected some unauthorized immigrants from deportation, at least temporarily. Legal protections Federal and state laws guarantee some basic protections for all workers, regardless of their immigration status. That includes the right to have a safe workplace and to earn the prevailing minimum wage where theyre employed, as well as overtime pay. Workers can report labor violations to the government, even if they are foreign-born and lack the legal authorization to work in the U.S. Its illegal for employers to retaliate for labor organizing at the workplace or for reporting minimum wage or overtime violations, unsafe working conditions, sexual harassment, or racial discrimination. To be sure, ensuring that these rights are respected is hard for workers who fear deportationespecially during an extremely anti-immigrant administration like the one Trump leads. And unauthorized workers dont have all the labor rights of citizens and permanent residents. For example, if an unauthorized worker is illegally fired for trying to form a union, they arent entitled to back pay or reinstatement as a citizen or an immigrant who has obtained the requisite authorization to work in the U.S. would be. This limitation essentially renders the right to organize a union meaningless for unauthorized immigrants if their employers retaliate. Obstacles and intimidation Enforcing immigrants rights is, of course, hard to do. Many immigrants dont speak English well. They may distrust the government. They could have trouble affording a lawyer or finding one who will represent them for free when faced with a labor law violation. Labor standards enforcement for unauthorized workers relies heavily on worker complaints, placing the burden on victims to speak out and submit a claim when faced with a violation. But they find it difficult to navigate through many layers of bureaucracy to file complaints with the proper authorities. Many undocumented workers also face intimidation from their employers, who might threaten to report them to immigration authorities if they complain to the Labor Department about unfair treatment or unsafe working conditions. This fear of deportation keeps many vulnerable workers silent about their exploitation. With only 650 investigators on staff at the Department of Labor in charge of enforcing minimum wage, overtime, and child labor lawsas of late 2024enforcement is mostly reactive. Only 1% of all farm employers were investigated annually, even before the second Trump administration began. Those numbers could climb if the Immigration and Customs Enforcement agency, or ICE, were to resume the large-scale enforcement raids the Biden administration halted in 2021. Previously, ICE had visited meatpacking plants and other employers from Texas to Tennessee that rely heavily on immigrant labor, in order to verify employment authorization documents. The authorities detain workers without valid papers, possibly deporting them. Their employers may face criminal fines and penalties and be ordered to stop hiring unauthorized immigrant workers. By early March 2025, the second Trump administration has not raided any large businesses. Instead, it has emphasized traffic stops and visits to small employers in communities with large numbers of unauthorized immigrants. But many big employers and communities are bracing for a wave of those operations. Wage theft and contributions to fund benefits they cant get Working conditions for immigrants without authorization were already difficult before Trump took office for a second time. Partly due to fear that their employers will report them to federal immigration enforcement authorities if they speak up, many of them experience wage theft, meaning that they dont get all of their pay and benefits, or their compensation falls below the minimum wage where they reside. Despite their typically low earnings, immigrants living without authorization who are employed in the U.S. pay more than $96billion in federal, state, and local taxes per year. They also contribute to the Social Security system even though they cant access these benefits when they retire, which the Internal Revenue Service requires of employers. Deferred Action for Labor Enforcement program Yet, over the years, many undocumented workers have come forward to defend their labor rights with the support of worker centers, labor unions, migrant-led organizations, and consulates from their countries of origin. Decades of increasingly visible grassroots advocacy for immigrant workers without authorization paid off in January 2023, when the Department of Homeland Security launched the Deferred Action for Labor Enforcement program. Known as DALE, it protects immigrant workers from exploitation and encourage reporting labor violations without fear of immigration consequences. This government program provides temporary deportation protections and work permits to eligible workers, with more than 7,700 work permits issued by October of 2024. The DALE program has encouraged many workers to come forward and report labor violations without fear of retaliation for speaking up, thus increasing minimum labor protections for all workers at thousands of workplaces. DALEs fate, however, is unclear now with Trump back in the White House. Xóchitl Bada is a professor of Latin American and Latino studies at the University of Illinois Chicago. This article is republished from The Conversation under a Creative Commons license. Read the original article.
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Scores of wildfires broke out across North Carolina, South Carolina and Georgia in early March 2025 as strong winds, abnormally dry conditions and low humidity combined to kindle and spread the flames. The fires followed a year of weather whiplash in the Carolinas, from a flash drought over the summer to extreme hurricane flooding in September, and then back to drought again. Storms on March 5, 2025, helped douse many of the fires still burning, but the Southeast fire season is only beginning. Wake Forest University wildfire experts Lauren Lowman and Nick Corak put the fires and the regions dry winter into context. Why did the Carolinas see so many wildfires? Most of North and South Carolina have been abnormally dry or in moderate drought since at least November 2024. Consistently dry conditions through the winter dried out vegetation, leaving fuel for wildfires. When the land and vegetation is this dry, all it takes is a lightning strike or a man-made fire and wind gusts to start a wildfire. Hurricanes did flood the region in late summer 2024, but before that, the Carolinas were experiencing a flash drought. Flash droughts are extreme droughts that develop rapidly due to lack of precipitation and dry conditions in the atmosphere. When the atmosphere is dry, it pulls water from the vegetation and soils, causing the surface to dry out. In August and September, Tropical Storm Debby and Hurricane Helene caused extensive flooding in the two states, but the Carolinas received little rainfall in the months that followed, leaving winter 2025 abnormally dry again. How unusual are fires like this in the region? Fires are historically fairly common in the Carolinas. Theyre a natural part of the landscape, and many ecosystems have evolved to depend on them. Carnivorous plants such as Venus flytraps and pitcher plants rely on frequent fire activity to remove shrubs and other plants that would grow over them and block the light. Even some wildlife depend on fire for their habitats and for food from the mix of native plants that regrow after a fire. The expected return periods for wildfires (how often fires have historically burned in a region) range from 1 to 10 years for the Piedmont and Coastal Plains in the east and 10 to 40 years in the Appalachian Mountains. However, many unplanned fires today are put out. That means underbrush that would normally burn every decade or so can build up over time, fueling more intense fires when it does burn. To avoid that overgrowth, land managers conduct annual prescribed fires to try to mimic that natural fire activity in a controlled way. These controlled burns are critical for removing vegetation that otherwise could provide additional fuel for more intense and damaging wildfires. Is dryness like this becoming more common? Extreme weather events are becoming more common across the U.S., including in the Southeast and the Carolinas. Increasing temperatures mean the atmosphere can hold more moisture, amplifying how much water it can draw from the land surface and eventually drop in heavier storms. That can lead to more extreme storms and longer dry periods. In humid regions like the Southeast, where there is an abundance of dense vegetation, periods of warm, dry conditions that dry out that vegetation will increase the risk of wildfire. According to the U.S. Drought Monitor, the southeastern U.S. experienced more droughts than other regions in the country in the first two decades of the 21st century. The weather variability also makes it harder to clear out forest undergrowth. Prescribed burns require that vegetation be dry enough to burn but also that winds are calm enough to allow firefighters to manage the flames. Studies show those conditions are likely to become less common in the Southeast in a warming world. Without that tool to reduce fuel, the risk of intense wildfires rises. Lauren Lowman is an associate professor of civil and environmental engineering at Wake Forest University. Nick Corak is a PhD candidate in physics at Wake Forest University. This article is republished from The Conversation under a Creative Commons license. Read the original article.
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