{"id":57743,"date":"2025-11-23T16:14:06","date_gmt":"2025-11-23T16:14:06","guid":{"rendered":"https:\/\/www.newsbeep.com\/us-fl\/57743\/"},"modified":"2025-11-23T16:14:06","modified_gmt":"2025-11-23T16:14:06","slug":"when-trade-routes-shift-so-do-clouds-florida-state-university-researchers-uncover-ripple-effects-of-new-global-shipping-regulations","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/us-fl\/57743\/","title":{"rendered":"When trade routes shift, so do clouds: Florida State University researchers uncover ripple effects of new global shipping regulations"},"content":{"rendered":"

\t\t\"AA large stacked container ship leaving the port of Cape Town, South Africa with Table Mountain and the city in the background. (Adobe Stock)\t\t<\/p>\n

When militia attacks disrupted shipping lanes in the Red Sea, few imagined the ripple effects would reach the clouds over the South Atlantic. But for Florida State University\u00a0atmospheric scientist Michael Diamond, the rerouting of cargo ships offered a rare opportunity to\u00a0clarify\u00a0a pressing climate question\u00a0\u2014\u00a0How much do cleaner fuels change\u00a0how\u00a0clouds\u00a0form?\u00a0<\/p>\n

\"AMichael Diamond is an assistant professor in Florida State University\u2019s Department of Earth, Ocean and Atmospheric Science (Devin Bittner\/FSU College of Arts and Sciences)<\/p>\n

In research published in\u00a0Atmospheric Chemistry and Physics<\/a>,\u00a0Diamond and FSU\u00a0Department of Earth, Ocean,\u00a0and Atmospheric Science\u00a0graduate student Lilli Boss showed that\u00a0new fuel regulations\u00a0that cut sulfur\u00a0by about 80 percent also\u00a0lowered cloud\u00a0droplet\u00a0formation by about\u00a067\u00a0percent compared with earlier, dirtier fuels.<\/p>\n

\u201cThe unexpected rerouting of global shipping\u00a0gave us\u00a0a\u00a0unique\u00a0opportunity\u00a0to\u00a0quantify\u00a0aerosol-cloud\u00a0interactions,\u00a0reducing\u00a0the largest source of uncertainty in global climate projections,\u201d\u00a0said\u00a0Diamond.\u00a0\u201cWhen your \u2018laboratory\u2019 is the atmosphere,\u00a0it\u2019s\u00a0not\u00a0every day\u00a0you can run experiments like this\u00a0one. It was\u00a0an invaluable opportunity to get a more\u00a0accurate\u00a0picture of\u00a0what\u2019s\u00a0happening on Earth.\u201d\u00a0<\/p>\n

The findings\u00a0could\u00a0help refine global climate models, offering policymakers and scientists\u00a0more\u00a0accurate\u00a0climate\u00a0predictions\u00a0and insight into\u00a0how environmental policy can protect human health.\u00a0<\/p>\n

CLEANER FUEL, FEWER CLOUDS
In January 2020, the\u00a0International Maritime Organization (IMO)<\/a>\u00a0mandated a major reduction in sulfur content in marine fuels to decrease air pollution. Aerosols from ship emissions,\u00a0especially\u00a0sulfate, influence cloud\u00a0formation\u00a0and\u00a0brightness, which in turn affect Earth\u2019s energy balance.\u00a0Referred to as aerosol-cloud interactions, these particles cause clouds to form with smaller, more\u00a0numerous\u00a0droplets, making them brighter and thus more reflective of sunlight. This creates a cooling effect, which has historically\u00a0masked about\u00a0one-third of the warming caused by greenhouse gases.\u00a0\u00a0<\/p>\n

But\u00a0air pollution\u2019s effects are marked by huge uncertainty and variability. Unlike long-lived greenhouse gases such as\u00a0carbon dioxide, or\u00a0CO2, which linger in the atmosphere for centuries, aerosols stay only for days or weeks. This short lifespan, coupled with the unpredictable nature of clouds, makes aerosol-cloud interactions the single largest source of uncertainty in global climate projections.\u00a0<\/p>\n

Diamond\u2019s\u00a0previous research<\/a>\u00a0had shown\u00a0that clouds in major shipping corridors were forming with larger and less\u00a0numerous\u00a0droplets after IMO 2020. Scientists are currently debating what role the resulting increase in sunlight absorbed over the ocean\u00a0played in the\u00a02023 and 2024\u00a0marine\u00a0heatwaves\u00a0in the Atlantic Ocean.\u00a0Different groups\u00a0also disagree about how much cloudiness declined after IMO 2020, with estimates ranging from a\u00a0relatively small\u00a010% change to a massive 80% decrease.\u00a0<\/p>\n

\"MapsMaps showing the values of nitrogen dioxide (NO2) observed in the troposphere, the lowest layer of Earth\u2019s atmosphere, in the Red Sea and the southeast Atlantic Ocean before and after disruptions to international shipping. Red markers in Map B represent locations of attacks on merchant ships during September\u2013October 2024. Boxes in Map D show where researchers measured nitrogen dioxide and cloud droplet concentration to study how changes to shipping fuels affected cloud formation.<\/p>\n

A \u2018NATURAL\u2019 EXPERIMENT
Beginning in\u00a0November\u00a02023, attacks\u00a0in the Bab al-Mandab Strait caused a sharp decline in Red Sea traffic and a surge in shipping around the Cape of Good Hope. As\u00a0a result, the South Atlantic region\u00a0\u2014 which\u00a0is\u00a0highly susceptible to ship emissions\u00a0because of\u00a0its persistent, low-lying clouds \u2014\u00a0experienced a sudden, massive increase in ship volume.\u00a0<\/p>\n

Because the rerouting was driven by conflict rather than weather or policy, researchers could\u00a0observe\u00a0how clouds changed in direct response to ship emissions alone.\u00a0Such clear cause-and-effect situations are almost impossible to create in controlled experiments, making this\u00a0a\u00a0valuable natural test case.\u00a0<\/p>\n

Satellite data revealed a clear increase in nitrogen dioxide, or NO2,\u00a0over the southeastern Atlantic\u00a0Ocean. NO2, a gas emitted by ship engines that was unaffected by the 2020 IMO fuel regulations, served as a reliable indicator of increased ship activity, confirming a surge in traffic through the region\u00a0and allowing\u00a0scientists to directly compare pre- and post-regulation conditions under heavy ship traffic.<\/p>\n

KEY FINDINGS
With\u00a0roughly twice\u00a0as many ships in operation\u00a0during 2024, the overall impact on cloud\u00a0droplet formation\u00a0was only slightly\u00a0weaker than before IMO 2020.\u00a0However, by comparing NO2, which was unaffected by the sulfur-reducing regulations, with cloud droplet number, which is sensitive to sulfur, Diamond and Boss found a 67%\u00a0reduction\u00a0\u00a0in\u00a0ships\u2019\u00a0cloud-altering\u00a0abilities\u00a0after the IMO regulations went into effect.\u00a0Their result\u00a0provides\u00a0further\u00a0strong evidence\u00a0that cleaner fuels have reduced shipping\u2019s influence on cloud\u00a0formation\u00a0and\u00a0helps\u00a0to\u00a0quantify\u00a0the relationship between pollution and cloud response,\u00a0which\u00a0is\u00a0an important constraint for improving climate\u00a0simulations.\u00a0<\/p>\n

WHY IT MATTERS
Quantifying how clouds respond to changes in aerosols\u00a0remains\u00a0one of the biggest challenges in\u00a0studying\u00a0the\u00a0climate.\u00a0<\/p>\n

This research\u00a0helps reduce the\u00a0error\u00a0bars that currently limit\u00a0estimates\u00a0of Earth\u2019s energy balance.\u00a0By narrowing this uncertainty, policymakers can make better-informed decisions about balancing environmental regulations with long-term climate goals. These findings also highlight the complex trade-offs in air-quality policy, showing how actions aimed at protecting human health can simultaneously reshape the planet\u2019s climate response.\u00a0<\/p>\n

Although these aerosols temporarily cool the planet, this comes at the cost of human health. Exposure to sulfur particles, potent air pollutants, is linked to respiratory and cardiovascular diseases. The IMO regulation is estimated to have\u00a0already\u00a0prevented tens of thousands of premature deaths.<\/p>\n","protected":false},"excerpt":{"rendered":"A large stacked container ship leaving the port of Cape Town, South Africa with Table Mountain and the…\n","protected":false},"author":2,"featured_media":57744,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[16],"tags":[232,234,233],"class_list":["post-57743","post","type-post","status-publish","format-standard","has-post-thumbnail","category-tallahassee","tag-tallahassee","tag-tallahassee-headlines","tag-tallahassee-news"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/us-fl\/wp-json\/wp\/v2\/posts\/57743","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/us-fl\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/us-fl\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/us-fl\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/us-fl\/wp-json\/wp\/v2\/comments?post=57743"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/us-fl\/wp-json\/wp\/v2\/posts\/57743\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/us-fl\/wp-json\/wp\/v2\/media\/57744"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/us-fl\/wp-json\/wp\/v2\/media?parent=57743"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/us-fl\/wp-json\/wp\/v2\/categories?post=57743"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/us-fl\/wp-json\/wp\/v2\/tags?post=57743"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}