Markus Andrews

My office at the University of California, Santa Barbara, looks out over the coastline. The United States’ first set of offshore oil platforms dot the skyline, the source of the 1969 oil spill that started the modern environmental movement. Enormous cargo ships traverse an ocean mega-highway, bringing goods from around the world and occasionally striking and killing whales. Surfers ride waves, sailing boats head for the islands and, on clear days, the beaches crawl with sunbathers. Recreational fishers cast their lines from the pier, commercial fishers set lobster traps along the coast, and a small mussel farm is hidden below the water just offshore.All of these activities are part of an intensifying ‘blue economy’, withdrawing value from the oceans that cover 71% of our planet. In many ways, this is a good thing. Shipping goods by sea is one of the most environmentally friendly ways to conduct global trade; farmed seafood is highly nutritious and often sustainable; offshore wind has the potential to generate huge amounts of green energy. But soon the already warming, already crowded ocean will reach the same points of no return that humans have reached on much of the land.Indeed, aquaculture, or farming seafood, has increased about 5% each year for the past 30 years, and experts anticipate that this growth will continue for the next few decades. Offshore wind is rapidly expanding; the United Kingdom is building a 1,000-square-kilometre metropolis of wind turbines off its coast, and China quadrupled offshore wind production just last year, adding the equivalent of roughly 17 nuclear power plants. An even more enormous area for wind farms has been proposed off the US Atlantic coast, at 7,000 square kilometres, nearly the size of Puerto Rico. And by 2050, the amount of goods travelling by sea is expected to triple as a result of increasing global population, wealth and trade.This is the dilemma at the centre of my research. For 20 years, I’ve studied how uses of the ocean cumulatively damage marine ecosystems, but also support vibrant human communities. From this work, I’ve come to feel there needs to be a collective deal to ensure that the economic benefits of the blue economy outweigh the ecological costs. I propose that any new ocean activities should be sustainable and also contribute to reduce pressure on the land.There is precedent for such give-and-take deals. In the United States and elsewhere, developers who encroach on wetlands and streams must create or restore equivalent habitats elsewhere, often at ratios of two-to-one or significantly greater (for example, 10 hectares of new wetland for every hectare destroyed). Carbon credits operate in a similar way; fees paid for emissions can go towards planting forests or building renewable energy infrastructure.A planetary deal of this kind should adhere to three constraints to be fair and effective.First, insist on real gains — not coincidental ones. If coal-fired power plants are already being phased out, this shouldn’t count as a balancing factor for new offshore wind. If conservation easements already protect fallow farmland, this can’t work as the counterpoint to new aquaculture farms.Second, actions need to be managed mainly through policy and regulations, not free markets. Left to their own devices, markets rarely incentivize sustainability or truly compensate for damage done to the environment. For example, evidence shows that increasing the amount of farmed fish in a free market does not reduce meat production.Finally, large corporations should bear the brunt of the costs of the planetary deal. Encouraging small operators often improves environmental justice while increasing local livelihoods and economic security by keeping owners and workers local. Compensatory requirements should be proportionally less for these small operators and progressively more for larger ones, analogous to the way income tax works in much of the world.So what might this planetary deal look like? For example, to receive a lease for a new 100-square-kilometre offshore wind farm, a company must restore twice as much coastal habitat. This restored habitat must be additional to any existing efforts to protect habitat, such as current global targets to protect 30% of land and sea.Or, for a new commercial offshore fish farm, enough land used for livestock should be permanently fallowed to remove a volume of livestock equivalent to the intended fish production. Such ‘habitat credits’ could be traded in the same way as carbon credits. The cattle farmer would get paid a tradable credit per reduced cattle head and hectare; an aquaculture company would need to purchase that credit to cover the increase in fish production.None of these options is politically easy — many will say that such policy and market regulation will slow progress and can be circumvented by determined bad actors — but in my opinion we must embrace them. They will require local, national and international coordination and enforcement, as well as public support. Science can help to inform and monitor effectiveness; government agencies will need to determinedly implement change. Moving forward with the blue economy without concomitant reductions in human pressures on both land and sea will simply sacrifice our oceans without planetary gain. That is no deal at all.

Competing Interests
The author declares no competing interests. More

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The availability of abundant green hydrogen (H2) fuels is important for decarbonization and the green energy transition. However, the production of large supplies of green H2 has so far been limited by the high energy consumption, high-purity water demand and the complexities of H2 transportation and distribution.
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Each year weather records are being broken around the globe; this boreal summer has seen heat records fall across Europe, America and Central Asia. These discernible effects of climate change cannot be ignored, as combined with global issues they endanger society and well-being.
The news headlines in the weeks of July 2022 have been dominated by reports of heatwave events in the UK, across Europe and the USA. The UK experienced record temperatures, with some locations exceeding 40 °C for the first time, while equally high temperatures were seen across the continent. Fires broke out in the extreme heat — extensive wildfires threatening lives and property, as has been seen all too often in recent years around the globe. In the USA, from the south to the north, temperatures exceeded 100 °F (37.8 °C) spanning the nation.
Credit: René Schmidt / Alamy Stock PhotoIn Spain, the recent heatwave was the first to be named, Zoe, as part of a trial in Seville1. It is standard practice for tropical cyclones to be named, allowing easy identification of different systems and providing early warning to those at risk, and this pilot of naming severe heatwaves aims to imitate that strategy and increase public awareness of impending heat risk. The system includes three tiers, and only time will tell how many top-tier, and therefore named, heatwaves will be seen this summer, and in the coming years.Outside the headlines seen here in the UK, there were extreme temperatures in Central Asia and China, and much of the globe saw heat anomalies pushing temperatures beyond the ‘norm’. These are not isolated events, normal is no longer that, as climate change and warming continue. Acknowledging the effect of climate change on average temperatures, earlier this year the UK Met Office updated their heatwave threshold classification — shifting from using the 1981–2010 average daily maximum mid-summer temperature to now using 1991–2020 as the base period (https://go.nature.com/3Q1Vhv2). Heatwaves occur when the temperature equals or exceeds this average for three consecutive days.Extended periods of hot weather put stress on societies and increases mortality risk. An attribution study showed that climate change increased heat-related mortality risk during the 2003 European heatwave — with the highest increase of approximately 70% occurring in central Paris2. Alongside the risks associated with heatwaves themselves, a recent study showed that higher ambient temperatures in Latin America increased the risk of premature death by 5.7% per 1 °C increase3. Another study considering data covering 43 countries and the period 1991–2018 showed that 37% of heat-related deaths in the warm seasons could be attributed to climate change4. This is further explored in a Feature, in our July issue, debating whether climate-related data should be included on death certificates for better understanding of climate change impacts on human mortality5.The immediate impact on human health from heat abates as weather systems pass, but these events as well as higher ambient temperatures have far-reaching consequences. Higher temperatures, in the short and long term, are raising concerns for water and food security, with food security currently of high concern as it is further exacerbated by the ongoing conflict in Ukraine. In Africa, there is ongoing wide-scale drought in the Horn of Africa, extending throughout East Africa, as well as drought in West Africa and the Sahel. Agriculture in these regions relies on rainfall and with four failed seasons in East Africa, and a drought touted as the worst in 40 years, there is insufficient water for crops to produce. Estimates place hundreds of millions of people at risk from this food crisis, with the situation in West Africa being exacerbated by conflict in the region.The risks of climate change continue to emerge, with those covered here just a small sample of those that have occurred, or are ongoing, in recent months. We have said it many times before but time is running out, there needs to be action and committed focus on addressing climate change as the new normal keeps shifting and we cannot adapt to keep pace. More

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Occoquan Watershed Monitoring Laboratory, The Charles E. Via Jr Department of Civil and Environmental Engineering, Virginia Tech, Manassas, VA, USAShantanu V. Bhide, Stanley B. Grant, Emily A. Parker, Megan A. Rippy & Adil N. GodrejCenter for Coastal Studies, Virginia Tech, Blacksburg, VA, USAStanley B. Grant, Megan A. Rippy & Todd SchenkDepartment of Geology and Earth System Science Interdisciplinary Center, University of Maryland, College Park, MD, USASujay KaushalFairfax Water, Fairfax, VA, USAGreg Prelewicz & Niffy SajiStormwater Planning Division, Public Works and Environmental Services, Fairfax, VA, USAShannon CurtisThe Charles E. Via Jr Department of Civil and Environmental Engineering, Virginia Tech, Blacksburg, VA, USAPeter Vikesland, Ayella Maile-Moskowitz, Marc Edwards & Kathryn G. LopezSchool of Public and International Affairs, North Carolina State University, Raleigh, NC, USAThomas A. BirklandUrban Affairs and Planning, School of Public and International Affairs, Virginia Tech, Blacksburg, VA, USATodd Schenk More

The Danuri probe will use multiple scientific instruments to probe properties of the Moon.Credit: NASA

By this time next week, South Korea’s first lunar probe will be on its way to the Moon. The probe, Danuri, which means ‘enjoy the Moon’, should arrive at its destination by mid-December and orbit for a year.Researchers are eager for Danuri, which took more than six years to build and cost 237 billion won (US$180 million), to begin revealing insights about aspects of the Moon ranging from its ancient magnetism to ‘fairy castles’ of dust sprinkled across its surface. Researchers also hope that the craft, officially called the Korea Pathfinder Lunar Orbiter, will find hidden sources of water and ice in areas including the permanently cold, dark regions near the poles.Scientists in South Korea say the mission will pave the way for the country’s more ambitious plans to land on the Moon by 2030. Success for Danuri will secure future planetary exploration, says Kyeong-ja Kim, a planetary geoscientist at the Korea Institute of Geoscience and Mineral Resources in Daejeon, and principal investigator for one of Danuri’s instruments, a γ-ray spectrometer. “Everybody is so happy and excited,” says Kim, describing the lines of people who waved goodbye to the orbiter — safely packed in a container — on its way to the airport on 5 July.Danuri was flown from South Korea to the United States, and is now in Cape Canaveral, Florida, preparing to be placed on a Falcon 9 rocket that will take it beyond Earth’s orbit on 2 August.“The spacecraft is ready to launch,” says Eunhyeuk Kim, project scientist for the mission at the Korea Aerospace Research Institute (KARI) in Daejeon, but he still sometimes worries about whether the team is truly ready. “Until the time of the launch, we will be checking all the systems over and over and over.”Within an hour of launching, the 678-kilogram spacecraft will detach from the rocket and KARI will take control of it, extending the craft’s solar panels and deploying its parabolic antenna.“It’s just so cool to see more and more countries sending up their own orbiters and adding to the global understanding of what’s going on on the Moon,” says Rachel Klima, a planetary geologist at the Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland, who is part of the science team.Fairy castlesDanuri will carry five scientific instruments. Among the most exciting is PolCam, which will be the first camera in lunar orbit to map the texture of the Moon’s surface using polarized light. Polarizers are popular for observations of Earth, such as those studying vegetation, but have not been sent to study the Moon, says Klima. By capturing how light reflects off the lunar surface, PolCam will be able to reveal characteristics such as the size and density of grains of dust and rock. This could help researchers to study unusual objects such as the tiny, porous towers of dust called fairy castle structures, says Klima. These structures can’t be reproduced on Earth because of its stronger gravity compared to the Moon, which makes them difficult to study.“It’s a ground-breaking instrument,” says William Farrand, a planetary geologist at the Space Science Institute in Boulder, Colorado, who will be working on PolCam data. Farrand hopes to use the data to study deposits of volcanic ash and improve understanding of the history of explosive eruptions on the Moon.Another widely anticipated instrument is ShadowCam, a highly sensitive camera provided by NASA that will take images of the permanently shadowed regions of the Moon, devoid of sunlight. The camera will need to rely on scattered light such as that from far-off stars to capture images of the surface topography.Since shortly after the Moon formed, volatile materials such as water from comets have been bouncing off its surface and becoming trapped in these very cold regions, says Klima. “We’ve got billions of years of Solar System history locked in the layers of these cold traps.” By giving researchers a view of the terrain in these regions, and identifying brighter regions that might be ice deposits, ShadowCam will be able to inform future landing missions to study that history, she says.MagnetismResearchers hope that data collected by Danuri’s magnetometer (KMAG) will help solve a mystery. The Moon’s surface displays highly magnetic regions; these suggest that for hundreds of millions of years in the Moon’s past, its core generated a magnetic field almost as powerful as Earth’s, through a process known as a dynamo, says Ian Garrick-Bethell, a planetary scientist at the University of California, Santa Cruz, who hopes to interpret KMAG data. But scientists are puzzled by how the Moon’s core, which is much smaller and proportionally farther from the surface than Earth’s, could have powered such an intense dynamo, and for so long. KMAG will take precise measurements of the Moon’s magnetic field to help them understand this.Garrick-Bethell hopes that towards the end of its life, the spacecraft will fly closer to the Moon to get even better measurements of the magnetic field. “The most exciting science would come if we flew closer to 20 kilometres.”The KARI team has not yet decided whether it will shrink Danuri’s orbit after the one-year mission is complete and eventually crash-land the craft on the Moon, says Eunhyeuk Kim. Alternatively, he says, the team could send the capsule into a higher orbit that could see it glide on for many more years. More