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A Different Kind of Climate Change Is Happening Under Your Feet

July 23, 2023

Oceans Are in Hot Water Because of Global Warming

Intense heat is breaking records all across the Northern Hemisphere from China to Arizona, Italy, and Greece. According to the UN, heat waves are going to become more common and threaten people in cities worldwide, especially those with low incomes, the elderly, and young children who are more likely to face the adverse effects of climate change.

Extensive bleaching of the soft coral Palythoa caribaeorum on Emerald Reef, Key Biscayne, Florida. Undated image  |  Credit: NOAA

However, heat waves are also occurring in the global seas with higher temperatures than any June, according to the Copernicus Climate Change Service. Since April, scientists at the National Oceanic and Atmospheric Administration (NOAA) have tracked a steady climb in ocean temperatures that is causing unprecedented heat stress in waters around Florida, the Caribbean, and the Gulf of Mexico.

Coral reefs off the Florida Keys, usually very colorful, are bleaching from the heat much earlier than is normal for this time of year. The corals get their color from algae that are food for the organisms, and when the water is too hot, they expel the algae which makes them appear white. The corals are still alive but could starve or succumb to disease.

Warming seas also affect fish reproduction, their migration patterns, and food availability. Rising ocean temperatures can trigger algal blooms and drive marine species toward the poles. The higher temperatures can alter ocean currents and weather patterns, fueling stronger atmospheric rivers, hurricanes, and cyclones, not to mention sea level rise as warmer water takes up more space.

Scientists are monitoring a large marine heat wave in the Pacific Ocean off the U.S. and Canadian west coast that started in May, and the BBC reports that extreme sea surface temperatures have also been occurring off Ireland, the UK, the Baltic Sea, and near New Zealand and Australia.

“Underground Climate Change” Is Occurring at an Alarming Rate

Heat is also a problem under cities. A new study from Northwestern University, finds a different kind of climate change is happening underground. Structures, like parking garages, basements, tunnels, and subways all continuously emit heat, which could prompt the ground to expand and contract, causing foundations to distort, tilt, move, crack, and settle.

Anjali Naidu Thota, a PhD student in Rotta Loria's lab, affixes a temperature sensor to a pipe in a basement beneath the Chicago Loop. | Credit: Northwestern University

In a statement, the researchers say there’s no immediate danger of buildings falling down, but the  “underground climate change” is occurring at an alarming rate. It’s not caused by greenhouse gases being released into the atmosphere but rather by human-built structures. Cities are warmer than rural areas because building materials trap heat from humans and solar radiation. Earlier studies showed that the shallow subsurface beneath cities warms by 0.1 to 2.5 degrees Celsius per decade. It can cause contaminated groundwater and health problems like asthma and heatstroke.  

The study focused on buildings in Chicago; however, the researchers said that underground climate change is common to almost all dense urban areas. They found that temperatures under the heart of downtown were frequently ten degrees Celsius warmer than under a nearby park. The lead author, Rotta Loria, said that buildings in the future should be designed to harvest the heat and use it as thermal energy, and in addition, the ground should be insulated from heat in new and existing buildings.

The study was published in the journal Communications Engineering.  

AI Bots Could Be a Force for Good in the Oceans

The conversation around artificial intelligence or AI is fraught with both anxiety and excitement. Some say the technology is an existential threat to humanity—helping to generate disinformation or leading to out-of-control machines that will become our overlords. Others promote its potential to develop new medical treatments and innovations.

A Taiwanese-flagged fishing vessel suspected of illegal fishing activity before being boarded by crew from the U.S. Coast Guard in 2009  | Credit: U.S. Coast Guard photo by Public Affairs Specialist 2nd Class Shawn Eggert

For scientists at the University of Southampton, the glass is half full. They’ve teamed up with ocean science experts RS Aqua to develop an AI-driven underwater bot that will be able to catch harmful activities like illegal fishing in the act. The system, codenamed MARLIN, will use underwater sensors to remotely surveil animal, human, and environmental activity anywhere in the ocean. Typical monitoring missions rely on ships crisscrossing the sea, but they say using bots instead of boats could potentially cut CO2 emissions by up to 75 percent.

MARLIN will use machine learning to distinguish ambient sound from that of, say, marine mammals and will be able to relay information in real time as opposed to current methods where instruments are left at sea for months before they are recovered and their data are assessed. The team says MARLIN’s rapid response could help ensure that, for example, offshore wind farm construction is sensitive to whales in the vicinity or that illegal activity in marine protected areas is detected and stopped.

Amsterdam Tells Tourists They Call a “Plague of Locusts” to Stay Away

If you’re wanting to visit Amsterdam, don’t plan to arrive by boat. The city council in the Dutch capital voted to close its central cruise-ship terminal, saying the polluting vessels are not in line with environmental and sustainability goals.

Cruise ships in Amsterdam  |  Credit: Jvhertum/Creative Commons

Part of the reason is Amsterdam’s ambitious target of becoming emission-free by 2030. A 2021 report found that one big cruise ship spewed the same amount of nitrogen oxides (NOx) in one day as 30,000 trucks, and another study by the European Federation for Transport and Environment which found 63 cruise ships owned by the Carnival Corporation emitted 43 percent more sulfur oxides than Europe’s 291 million cars in 2022.

That really adds up when you consider that Amsterdam—one of the largest cruise ports in Europe—sees over 100 ships annually, which one council member likened to a “plague of locusts” descending on the city, according to the BBC. The comment reflects the general mood of locals and lawmakers, who feel that there are just too many people visiting Amsterdam—over 20 million just last year alone—many of whom they describe as “nuisance tourists” attracted to the city’s reputation as a place to party.

The move by Amsterdam is part of a trend. In 2021, Venice, Italy, put the kibosh on cruise ships in its city center to protect the fragile ecosystem, and Barcelona, Spain, is also curbing the number of ocean liners arriving there. All three cities say cruise ship passengers make too large an impact on local infrastructure and contribute little to local economies.

Cruise ships aren’t the only mode of transport in the crosshairs. The Netherlands recently announced plans to cut the number of flights at Amsterdam’s Schiphol Airport to address the climate crisis.

The timeline to ban cruise ships and moor them somewhere else outside the city is still being determined, but eventually locals will perhaps be able to say “less is moor.”