Polar code agreed to prevent Arctic environmental disasters

Karl Mathiesen in the Guardian (UK): The international body in charge of sea safety adopted measures on Friday to protect people and the environment during a predicted shipping rush in the Arctic. But environment groups and insurers said the International Maritime Organisation (IMO) Maritime Safety Committee had failed to address key issues including a proposed ban on heavy fuel oil and how to safeguard against cowboy operators.

The committee, which met in London this week, signed off on the Polar Code and various amendments to the Safety of Life at Sea (Solas) convention. These changes, which include mandatory requirements for ship design, crew training and search and rescue protocols, are expected to be ratified by the full IMO next year and come into force in 2017.

Melting sea ice due to global warming and pressure to cut costs makes the Arctic commercially enticing to shipping companies who want to avoid the circuitous, pirate-ridden voyage from China to Europe via the Suez Canal. Tourism, fishing and fossil fuel operations are also looking toward one of the world’s most fragile and extreme environments.

Evan Bloom, director of the US State Department’s Office of Ocean and Polar Affairs said: “More and more people are going to be in the Arctic for one reason or another. In the future there may be [more] fishing vessels... There will be more and more tourism. There will be more and more commerce.” He says this increases the likelihood of something going wrong in a region where there is currently very little capability to respond in either a search and rescue or environmental clean-up capacity.

...According to insurer Allianz, Russia predicts a 30-fold increase in shipping by 2020 and an ice-free Northern Sea Route by 2050. China has suggested that by 2020, 5-15% of its trade value - close to $500bn - could pass through the Arctic....

Sea ice off Baffin Island, via NASA

Winds of change for the shipping sector

A press release from the University of Manchester: Wind propulsion such as kites and Flettner rotors could offer a viable route to help cut CO2 emissions in the shipping sector, according to Dr Michael Traut, a Research Associate from The University of Manchester.

Speaking at the ‘Shipping in Changing Climates: provisioning the future’ Conference in Liverpool today (Thursday), Dr Traut will present research that uses a new model to couple wind-power technologies with weather data to show how in theory, and with supporting incentives, wind energy could cut CO2 and fuel use by as much as 50% on smaller cargo vessels up to 5,000 dead weight tonnes. This would also have a knock-on impact of cutting sulphur and nitrogen oxide and dioxide emissions by reducing the total amount of fuel burnt.

The study, to be presented in a session entitled ‘Future Shipping Propulsion’, will be discussed alongside presentations from more than 30 other speakers from across academia and the shipping industry. All the speakers will be exploring new issues and opportunities on the horizon for the industry in meeting the challenges faced by climate change.

The conference, sponsored by Lloyd’s Register and Shell, is integral to an Engineering and Physical Sciences Research Council (ESPRC) and industry-funded consortium project, and will bring together an audience made up of industrialists, policymakers and academics to debate how climate change may impact on the shipping sector worldwide.

The Shipping in Changing Climates project combines expertise from two substantial existing shipping research projects with two additional research partners. Project lead Professor Paul Wrobel, from UCL, said: “Our vision is to create an enduring, multi-disciplinary and independent research community strongly linked to industry and capable of informing the policy making process by developing new knowledge and understanding of the shipping system, its energy efficiency and emissions, and its transition to a low carbon, more resilient future.”...

Flettner rotors powering a German vessel, RoLo cargo ship E-Ship 1. Shot by kaʁstn Disk/Cat, Wikimedia Commons, under the Creative Commons Attribution-Share Alike 3.0 Germany license

Global warming will open Arctic to invasive species

Smithsonian Science: For the first time in roughly 2 million years, melting Arctic sea ice is connecting the north Pacific and north Atlantic oceans. The newly opened passages leave both coasts and Arctic waters vulnerable to a large wave of invasive species, biologists from the Smithsonian Environmental Research Center assert in a commentary published May 28 in Nature Climate Change.

Two new shipping routes have opened in the Arctic: the Northwest Passage through Canada, and the Northern Sea Route, a 3000-mile stretch along the coasts of Russia and Norway connecting the Barents and Bering seas. While new opportunities for tapping Arctic natural resources and interoceanic trade are high, commercial ships often inadvertently carry invasive species. Organisms from previous ports can cling to the undersides of their hulls or be pumped in the enormous tanks of ballast water inside their hulls. Now that climate change has given ships a new, shorter way to cross between oceans, the risks of new invasions are escalating.

 “Trans-Arctic shipping is a game changer that will play out on a global scale,” said lead author Whitman Miller. “The economic draw of the Arctic is enormous. Whether it’s greater access to the region’s rich natural resource reserves or cheaper and faster inter-o
cean commercial trade, Arctic shipping will reshape world markets. If unchecked, these activities will vastly alter the exchange of invasive species, especially across the Arctic, north Atlantic and north Pacific oceans.”

The first commercial voyage through the Northwest Passage—a carrier from British Columbia loaded with coal bound for Finland—occurred in September 2013. Meanwhile, traffic through the Northern Sea Route has been rising rapidly since 2009. The scientists project that at the current rate, it could continue to rise 20 percent every year for the next quarter century, and this does not take into account ships sailing to the Arctic itself....

The Russian icebreaker, Captain Demidov

Rescue of stranded Antarctic ship stalls--shades of Shackleton!

Terra Daily via AFP: A Chinese icebreaker has failed to break through thick ice to free a ship carrying scientists and tourists stranded off Antarctica, forcing Australian authorities to look at other rescue options Saturday. The Australian Maritime Safety Authority (AMSA), which is coordinating the rescue of the Russian passenger ship MV Akademik Shokalskiy, said the icebreaker came within six-and-a-half nautical miles of the ship but had to stop.

"The Chinese vessel unfortunately encountered some heavy ice that it's not capable of breaking through," AMSA spokeswoman Andrea Hayward-Maher told AFP. "So unfortunately it won't be able to continue through to the Akademik Shokalskiy. It's making its way back."

"The rescue... unfortunately has stalled."  The Russian ship, with 74 people on board, has been trapped in ice about 100 nautical miles east of the French base Dumont d'Urville since Tuesday.

The Chinese vessel came tantalisingly close to the trapped ship, with those on board reporting they could see it in the distance, but was forced to turn back to open sea once it realised it could not break through.

"At the horizon in the east I can see the Chinese icebreaker that we were hoping was going to be here within hours cutting us a path out of this place but it just couldn't make it," science journalist Andrew Luck-Baker onboard the Russian ship told the BBC.

It slowed down to about half a knot and has decided to go back to where the sea begins and wait for the arrival of an Australian icebreaker. The idea now is for the two of them to come together in parallel towards us, cutting a wider path."

Three vessels with icebreaking capability, including Australia's Antarctic resupply ship Aurora Australis and French vessel L'Astrolabe, were ordered to the area to attempt to rescue the vessel once the distress signal was sent....

Frank Hurley's photograph of the Endurance being crushed by the ice in Antarctica, 1915 

Arctic at risk from invasive species

Christopher Ware in the Ecologist: As the Arctic ice melts, new shipping routes are opening up for tourism, mining and other commercial purposes, cutting journey times and fuel costs. And as Christopher Ware reports, a new danger arises - invasive alien species disrupting fragile Arctic ecosystems ...

More shipping is sailing through thawing Arctic waters, but while these northern routes might provide opportunities for tourism, mining and cutting down delivery times, the ships may also carry stowaways on board, introducing invasive species to pristine Arctic waters.

These findings were recently published in the journal Diversity and Distributions, from research by myself and colleagues at Tromsø University Museum in Norway, University of Tasmania in Australia, and Aarhus University in Denmark. The study focused on the Svalbard archipelago in the Norwegian high-Arctic - best known for being home to the northernmost post office in the world and some 3,000 polar bears.

....Wherever humans have travelled over the past centuries they have, deliberately or accidentally, taken creatures and plants with them. Exotic grasses now grow on Antarctica, European crabs live on both North American coasts, and Australia is filled with many millions of non-native rabbits, boar, toads and camels.

By filling and discharging ballast tanks, organisms are sucked in, transported and then deposited in other parts of the world, as are creatures that live on the bottom of the ship’s hull. Ships are responsible for most of world’s spread of invasive marine species.

Svalbard has experienced increased shipping over recent decades from tourism, scientific research, and mining. The ports there are far from the scale of those in Rotterdam or Singapore - there are more snow mobiles delivered to Svalbard every year than there are ships visiting - but nevertheless more than 500m tonnes of ballast water are discharged off Svalbard every year, from some of the 200 visiting vessels....

The tundra at Svalbard, shot by Billy Lindblom, Wikimedia Commons via Flickr, under the Creative Commons Attribution 2.0 Generic license

A new era for Arctic shipping? Chill, please

John Higginbottom in the Globe and Mail (Toronto): Last month, a humble marine bulk carrier made history transiting the Northwest Passage, opening a new chapter in Arctic shipping over the top of North America. Reactions depended on where people sit.

A U.S. federal government official helpfully discouraged Canadian focus on the Northwest Passage while we’re at odds over its legal status, something lawyers might or might not clear up by the end of the century. For those who favour Arctic development, the voyage offers a tempting glimpse of the new maritime economy oceanic warming may bring. Environmentalists foresee an apocalypse. For those with a love of history, the voyage recalls centuries of exploration and sacrifice by iron sailors in wooden ships searching for a shorter trade route between Europe and Asia.

A balanced and realistic reaction is in order. Recall the facts: The Nordic Orion, a Danish-American vessel, picked up coal from a dock in Vancouver, sailed north around Alaska, through the Canadian Arctic archipelago and then south past Greenland to deliver its cargo to Finland.

...Still, it will be years before the NWP is truly “open for business,” even for specialized cargo and ships like the Arctic Orion.... Sadly, Canada lacks deep-water ports, icebreakers, state-of-the-art navigation aids, search and rescue facilities, oil spill prevention and mitigation capacity and fully modern charts that would facilitate destination, cruise, fishing and trans-polar shipping.

The gradual and careful opening of the North American Arctic Ocean could bring great benefits to local people, traders, shippers and investors, while providing better destination service and shorter and greener routes to and from Asia from North America’s east coast, and to and from Europe from our west coast....

The Swedish ice breaking ship Oden, shot by Henning Grote, Wikimedia Commons via Flickr, under the Creative Commons Attribution-Share Alike 2.0 Generic license

First ship through the Arctic carried coal

John McGarrity and Henning Gloystein in Reuters: A large sea freighter completed a voyage through the hazardous Arctic Northwest Passage for the first time on Friday as global warming opens routes that mariners have wanted for centuries.

The 75,000 deadweight-ton Nordic Orion, built in 2011, left the Canadian Pacific port of Vancouver in early September with a cargo of coking coal and is scheduled to arrive in the Finnish port of Pori on October 7, according to AIS shipping data.

"The Northwest Passage is more than 1,000 nautical miles shorter than the traditional shipping route through the Panama Canal and will save time, fuel and reduce carbon dioxide emissions, but even more importantly increase the amount of cargo per transit 25 percent," said Nordic Bulk Carriers, the Danish owner of the ship...

A coal loading depot in Inverkeithing, shot by Richard Webb, Wikimedia Commons via Geograph UK, under the Creative Commons Attribution-Share Alike 2.0 Generic license 

A container ship is traversing the northern sea route for the first time

Mat McDermott in Motherboard: An important historic event is in the making: For the first time a container ship will sail the Northern Sea Route through the Russian Arctic, traveling from China to Amsterdam. The journey, which began on August 8 and is expected to be completed on September 11, is only now possible due to high levels of Arctic sea ice melt that have occurred in the past several years.

The Barents Observer reports the 19,000-ton Yong Sheng, a container ship operated by China Ocean Shipping Company (COSCO)—though not the exact one pictured at the top of this article—left port in China in the first week of August and is now in the Russian Arctic.

For a few years now the Northern Sea Route has become passable in summer, at least by vessels designed for icy Arctic waters. Last summer an icebreaker became the first Chinese vessel to make the passage. In 2010, a Norwegian vessel carrying iron ore to China became the first non-Russian vessel to complete the journey.

This year alone, Russia has allowed 204 ships of varying types to make the journey, with COSCO gaining permission to make two more sailings this year along the route. Russia's largest shipping company already offers non-containerized shipping along the route for six months of the year.

The Northern Sea Route, also known as the Northeast Passage, runs along the entire northern coast of Russia, across Siberia, before emptying into the Bering Strait and Pacific Ocean. Historically it has been ice free in parts for about two months of the year, but in recent years it has become passable because of climate change on Arctic ice melt....

A highly important map regarding the early search for a Northeast Passage. This remarkable map was drawn in 1601 by Theodore de Bry to describe the ill fated third voyage of the Dutch explorer William Barentsz in search of the Northeast Passage. The map depicts the Island of Nova Zemba, or Novaya Zemlya, in the Russian Arctic along with two stunning compass roses, numerous rhumb lines, and a multitude of seals and sea monsters.

Shipping firms warn of haze danger in Malacca Strait

Terra Daily via AFP: Shipping companies warned Friday that the haze emanating from forest fires in Indonesia could lead to accidents in the busy Malacca and Singapore straits, risking a potentially devastating oil spill.

The Singapore Shipping Association (SSA) said more than 140 ships, including oil tankers and passenger ferries, navigate the narrow waterways on any given day and reduced visibility due to the smog has made conditions dangerous.

"The SSA is gravely concerned with the effects of the worsening hazy conditions on the safe navigation of ships through the Straits of Malacca and Singapore," it said. Daniel Tan, the trade body's executive director, said the Malacca and Singapore straits are among the busiest and narrowest shipping lanes in the world...

Smoke from Indonesian fires, view by NASA on June 19, 2013

Global warming will open unexpected new shipping routes in Arctic

Meg Sullivan in the UCLA Newsroom: Shipping lanes through the Arctic Ocean won't put the Suez and Panama canals out of business anytime soon, but global warming will make these frigid routes much more accessible than ever imagined by melting an unprecedented amount of sea ice during the late summer, new UCLA research shows.

"The development is both exciting from an economic development point of view and worrisome in terms of safety, both for the Arctic environment and for the ships themselves," said lead researcher Laurence C. Smith, a professor of geography at UCLA.

The findings, which explore accessibility during the Arctic's most navigable month of the year, September, appear in the latest issue of the scholarly journal Proceedings of the National Academy of Sciences Plus. The first thorough assessment of trans-Arctic shipping potential as global temperatures continue to rise, the study is based on independent climate forecasts for the years 2040 to 2059.

By mid-century, even ordinary shipping vessels will be able to navigate previously inaccessible parts of the Arctic Ocean, and they will not need icebreakers to blaze their path as they do today, the researchers found.

"We're talking about a future in which open-water vessels will, at least during some years, be able to navigate unescorted through the Arctic, which at the moment is inconceivable," said co-author Scott R. Stephenson, a Ph.D. candidate in the UCLA Department of Geography.

Just as surprisingly, the Arctic ice sheet is expected to thin to the point that polar icebreakers will be able to navigate between the Pacific and Atlantic oceans by making a straight shot over the North Pole, Smith and Stephenson predict. "Nobody's ever talked about shipping over the top of the North Pole," Smith said. "This is an entirely unexpected possibility."...

Red lines indicate the fastest available trans-Arctic routes for Polar Class 6 ships (moderate-capability icebreakers such as those used today in the Baltic), and blue lines indicate the fastest available routes for common open-water ships. Where overlap occurs, line weights indicate the number of successful transits following the same route. Dashed lines reflect currently existing sovereignty boundaries. The white backdrop indicates period-averaged sea ice concentration.  (Courtesy of Proceedings of the National Academy of Sciences)

Not enough ships able to flush out invasive species before they reach port

Science Daily: Invasive species have hitchhiked to the U.S. on cargo ships for centuries, but the method U.S. regulators most rely on to keep them out is not equally effective across coasts. Ecologists from the Smithsonian Environmental Research Center have found that ports on the East Coast and the Gulf of Mexico are significantly less protected than ports on the West Coast.

Invaders are frequently introduced across oceans and along coastlines through the ballast water in ship hulls, water that often includes plankton and larval stages of marine and estuarine species. Large vessels need this water for balance as they load and unload cargo. However, by dumping ballast water in their ports of entry, they accidentally bring in new species that can alter or damage the local ecosystem. In 2004 policymakers thought they had found a solution: have cargo vessels exchange their ballast water in the open ocean, at least 200 nautical miles from land. This method, called "open-ocean exchange," flushes out or kills potential invaders by exchanging coastal water for water from the deep ocean.

But some ships do not use the practice and many more cannot without veering drastically off course. In perhaps the most comprehensive study to date, Whitman Miller and a team of scientists from SERC looked at all international ships entering the contiguous U.S. over three years. Published in the journal BioScience, the study analyzed approximately 105,000 vessel reports from January 2005 to December 2007. While most ships opted not to discharge their ballast water at all, a substantial number continued to dump unexchanged or improperly exchanged water into their ports of entry.

Not all coasts are affected equally. The Gulf of Mexico and the East Coast received much larger fractions of unexchanged ballast water than the West Coast. Roughly 5 percent of the ballast water discharged on the West Coast had not undergone open-ocean exchange. By contrast 21 percent of the discharged water in the Gulf and 23 percent on the East Coast went unexchanged....

US Coast Guard image of ship pumping ballast water

The opening of Arctic sea routes

By Joshua Ho in Eurasia Review: ... The effects of climate change as a result of global warming include the increase in adverse weather events; water shortages; sea level rise and consequential flooding and destruction of coastlines. There will be a decrease in crop yields due to increasing temperatures and a reduction in water supply; and an increase in temperature-related illnesses and deaths.

Some traditional activities like agriculture, fisheries and tourism might be reduced or even disappear altogether in regions that are heavily affected by climate change. Societies that are not able to adapt to climate change will experience great suffering. However, there are some positive aspects associated with global warming. The opening of new sea lanes that can reduce transit times between destinations is one of them.

According to the Arctic Council’s Arctic Marine Shipping Assessment (AMSA) 2009 Report, there is a possibility of the Arctic Ocean becoming ice-free for a short period in summer as early as 2015. This would mean the disappearance of multi-year ice, which would not last during the summer melt season. Notwithstanding the prognosis of an early opening of Arctic routes, like the Northern Sea Route, the AMSA assesses that transit traffic in the Northern Sea Route may not be more regular until around 2025.

AMSA estimates that regular trans-polar summer transport (four months) will occur towards the middle of the century, from 2040 onwards. When this happens, tremendous shipping benefits would accrue as transiting the Northern Sea Route above Russia between the North Atlantic and the North Pacific would trim about 5,000 nautical miles and a week’s sailing time from that via the Suez Canal and Malacca Strait. Financial savings associated with using this shorter route are estimated at about USD 600,000 per vessel. This may have an adverse impact on existing regional hub ports like Singapore which have long been a nexus of East-West shipping. Despite the threats that could be presented to a transit hub port like Singapore, there are also opportunities which could be capitalised on....

The Swedish icebreaker Oden, shot from NOAA

With global warming, Arctic access will diminish by land but improve by sea

Meg Sullivan in the UCLA Newsroom: Global warming over the next 40 years will cut through Arctic transportation networks like a double-edged sword, limiting access in certain areas and vastly increasing it in others, a new UCLA study predicts. "As sea ice continues to melt, accessibility by sea will increase, but the viability of an important network of roads that depend on freezing temperatures is threatened by a warming climate," said Scott Stephenson, a UCLA graduate student in geography and the study's lead author.

Winners are expected to be coastal communities, coastal resource-extraction operations, tourism, fishing, and shipping concerns, the researchers say. Potential losers include inland mining and timber operations, inland oil and gas drilling, and smaller inland communities, often inhabited by indigenous peoples. Even northern Canada's famed Tibbitt–Contwoyto "diamond road," said to be the world's most lucrative ice road, is expected to suffer, according to the researchers. The findings appear in the June issue of the peer-reviewed scholarly journal Nature Climate Change.

"Popular perception holds that climate warming will mean an opening up of the Arctic, but our study shows that this is only partly so," said co-author Laurence C. Smith, a UCLA professor of geography and author of "The World in 2050: Four Forces Shaping Civilization's Northern Future" (Dutton Books, 2010). "Rising maritime access for ships will be severely countered by falling vehicular access on land."

Along with veteran UCLA geographer John A. Agnew, Stephenson and Smith integrated existing accessibility models for the Arctic with the National Center for Atmospheric Research's widely used climate models for the coming century. The researchers averaged month-to-month accessibility rates for two time periods: 2010 to 2014 and 2045 to 2059. They then compared the two scenarios.

…A major casualty will be temporary ice roads, according to the study. Constructed across frozen ground, lakes, rivers and swampy areas using compacted snow and ice and applied sheets of ice, these roads currently provide access to vast swaths of inland terrain where the construction of all-weather roads is not economically viable….

Arctic shipping map from the UCLA Newsroom

Seaports need a plan for weathering climate change

EurekAlert: The majority of seaports around the world are unprepared for the potentially damaging impacts of climate change in the coming century, according to a new Stanford University study. In a survey posed to port authorities around the world, the Stanford team found that most officials are unsure how best to protect their facilities from rising sea levels and more frequent Katrina-magnitude storms, which scientists say could be a consequence of global warming. Results from the survey are published in the journal Climatic Change.

"Part of the problem is that science says that by 2100, we'll experience anywhere from 1.5 to 6 feet of sea level rise," said the study's lead author, Austin Becker, a graduate student at Stanford. "That's a huge range."

Port authorities, like many government agencies and private companies, have to make tough financial decisions when it comes to funding infrastructure, he said. They need accurate information from scientists about what to expect, so that they can plan accordingly. Building a structure to withstand a 6-foot sea level rise would cost much more than trying to accommodate a 1.5-foot rise, said Becker, a doctoral candidate in the Emmett Interdisciplinary Program in Environment and Resources at Stanford.

In 2009, Becker distributed 160 surveys to members of the International Association of Ports and Harbors and the American Association of Port Authorities – the first worldwide survey of port authorities to address climate change adaptation. A total of 93 agencies representing major seaports on every continent, except Antarctica, responded. The majority of respondents ranked sea level rise and increased storm events associated with climate change high on their list of concerns. However, only 6 percent said that they intend to build hurricane barriers within the next 10 years, and fewer than 18 percent had plans to build dikes or other storm protection structures….

Claude Lorrain painting of a seaport, 1638

Russia dusts off old plans to open the Northeast Passage for sea trade with Asia

Jonathan Manthorpe in the Vancouver Sun (Canada): The plague of pirates preying on Asia's sea links to Europe and the prospects of opportunities presented by global warming have prompted Russia to dust off some old plans that have been lying in filing cabinets since the collapse of the Soviet Union.

The shortest route by some 3,000 nautical miles between the throbbing workshops of the Far East and Southeast Asia and the hypermarkets of Europe is not the current course through the traffic jams of the Malacca Straits and the high-risk transit past the Horn of Africa to the Suez Canal.

It is what the Russians call the Northern Sea Route and what those with a British-centric view of global maritime exploration are more likely to still call the Northeast Passage. This route runs from the Barents Sea north of Norway and the Russian port of Murmansk -- a city, incidentally, attacked and burned by a Royal Navy captain ancestor of this writer during the Crimean War -- along the Arctic coast of Siberia and down through the Bering Strait to Asia.

This route was used extensively during the Soviet period with the help of nuclear-powered icebreakers, because parts of the sea are only ice-free for two months a year in late summer. Use of the northern route dwindled to nothing after the collapse of the Soviet Union and the two decades of internal turmoil needed to reimpose political stability and nationwide economic growth. The reawakening of Russia's Arctic consciousness came with the construction and opening in 2008 of an extraordinary oil terminal 22 kilometres offshore at Varandey in the eastern Barents Sea….

North of the western Russian mainland lies the island archipelago of Novaya Zemlya. The archipelago is situated in the Arctic Ocean, between the Barents Sea to the west and the Kara Sea to the east. Satellite image from NASA

Geoengineering takes a ride in shipping lanes

Pacific Northwest National Laboratory: Ships blowing off steam are helping researchers understand how manmade particles might be useful against global warming. New results from modeling clouds like those seen in shipping lanes reveal the complex interplay between aerosols, the prevailing weather and even the time of day the aerosol particles hit the air, according to research presented today at the American Association for the Advancement of Science's annual meeting.

"We've seen ship tracks affect the reflectivity of clouds," said Phil Rasch, chief climate scientist at the Department of Energy's Pacific Northwest National Laboratory in Richland, Wash. "We want to know if we can do the same thing when we want to, on purpose, and how that might be helpful in countering some of the effects of global warming. "We decided to see how the reflectivity of clouds is influenced by particles in a very detailed model that treats clouds much more realistically than we are able to do in a typical climate model."

Reflecting sunlight back into space prevents that energy from hitting Earth's surface. So brighter clouds could have an overall cooling effect compared to darker ones. A handful of research groups in the US are exploring geoengineering, or the intentional modification of Earth's climate, in hopes of developing tools that might be used to lower global temperatures if atmospheric greenhouse gases reach levels that might produce disastrous climate change.

…"Do the brighter and darker parts cancel each other out?" asked Rasch. To find out, the group performed some exploratory computer simulations to determine the net effect of increased aerosols. His team simulated three ships chugging along in a 93-mile by 37-mile block of the Pacific Ocean a few hundred miles southwest of Los Angeles.

The team showed that introducing additional particles into the model near the surface — as proposed for geoengineering — would make the clouds significantly more reflective than they would otherwise be, in certain situations. They found that if the clouds were already drizzling then the new particles would not brighten them very effectively….

A tanker (Abqaiq) takes on oil from Iraq's Mini-Al Basrah offshore terminal. Shot by an employee of the US government