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Controversy pervaded the June 2022 UN Ocean Conference, with partisan alliances forming around burgeoning environmental and social issues. Yet, out of the talks, emerged strong aspirations across UN states and other stakeholders to restore and protect the ocean.Sustainable Development Goal (SDG) 14, to conserve and sustainably use the oceans, seas and marine resources, has elicited broad ambition among many sectors of society. The UN Ocean Conference (UNOC) was established to promote global progress towards achieving SDG 14, providing a forum for stakeholders to address disparate but interlinked concerns including ocean pollution, resource extraction and climate. In June 2022, ocean stakeholders spanning politics, science, industry and civil society met in Lisbon for the second high-level UN Ocean Conference, which was chaired by the presidents of Kenya and Portugal. Eight themes were discussed in general sessions — framed as interactive dialogues — although these mainly comprised prepared statements and lacked spontaneous dialogue. Prominent topics included conservation, deep-seabed mining, and the triple nexus of ocean–climate–biodiversity, distributed justice and ocean finance. More

Lead levels in a lead pipe-free campusFigure 1 (number of dispenser and faucet samples not stacked but overlapped) shows the distribution of Pb levels in the 558 water samples collected from POU dispensers (n = 204) and faucets (n = 354) during the survey. The distribution of total number of samples collected using different protocols is shown in Supplementary Table 1. Table 1 shows the water quality parameters of the sample water. Among the total 558 samples collected, regardless of sampling protocols used, 89 samples (16%) had Pb levels greater than the Taiwan EPA standard value (or the WHO guideline value) of 10 μg/L.Fig. 1: Pb levels in water samples.Distribution of Pb levels in water samples collected from POU dispensers (n = 204) and faucets (n = 354). Dotted line refers to the WHO guideline value of 10 μg/L for Pb in drinking water.Full size imageTable 1 Water quality parameters of samples.Full size tableSamples with Pb levels above 10 μg/L are considered “unsafe” in this study. Since the number of samples collected from dispensers and faucets varied, a percentage was used to represent the proportion of unsafe samples. In this regard, 66 out of 354 (19%) samples from faucets and 23 out of 204 (11%) samples from dispensers were not safe for consumption. Hence, faucet samples were approximately twice as likely to be contaminated as dispenser samples. As expected, the use of POU dispensers could effectively reduce Pb levels, but not always below the regulatory standard of 10 μg/L. Possible reasons include inadequate removal efficiency of dispenser filters and Pb-containing components in the filter system. The extent of Pb reduction (or unlikely addition) through a dispenser was, however, not determined in this study. Although POU dispensers have become necessary in delivering safe drinking water, the occurrence of unsafe samples from such dispensers showed that water from dispensers does not always meet the regulatory standard. The results also indicated that Pb contamination issues could be prevalent even if no aged Pb pipes were present. For faucet samples, the Pb sources are most likely Pb-containing plumbing materials such as brass fittings and Pb solders5,6. Although regulations of Pb in plumbing materials have evolved with time, legacy plumbing materials may still be present in the buildings. Harvey et al.5 collected water samples from kitchen tap fittings in Australia and demonstrated that Pb-containing fittings could significantly contribute to Pb in drinking water. Similarly, Ng and Lin6 concluded that brass fittings were the main source of Pb in drinking water in a simulated copper pipe premise plumbing.All buildings except Building VIII (Supplementary Table 1) had at least one sample from the faucet and dispenser exceeding 10 μg/L Pb. Building VIII is the only building without any unsafe samples from the dispensers. Buildings VII had the highest percentage of samples that were unsafe (24%), followed by buildings VI (23%), IV (17%), and III (16%) (Supplementary Table 2). Although the percentage of unsafe samples from faucets was approximately twice that from dispenser samples (Fig. 1), a higher proportion of faucet samples compared to dispenser samples collected in a building did not always correspond with an increase in the proportion of unsafe samples among the buildings (Supplementary Table 2). For example, Building III had more samples collected from faucets (70%) than Building VII (63%). Still, the proportion of unsafe samples in Building III (16% of samples) was less than in Building VII (24% of samples).Figure 2 shows the median total Pb concentration for dispensers and faucets in the eight buildings surveyed. The median Pb level ranged from 1.3 to 5.7 µg/L and 2.2 to 5.7 µg/L for dispenser and faucet samples, respectively. The median Pb level for dispenser samples was lower than faucet samples in six of the eight buildings. The difference in medians between dispenser (filtered) and faucet (unfiltered) samples were significantly different using t test (p value More

RESEARCH HIGHLIGHT
21 September 2022

Groundwater stores on the Tibetan plateau have risen recently, but the bad news is that thawing snow and ice are the source. More

Empirical data are crucial for developing risk-management and governance strategies for floods and droughts (H. Kreibich et al. Nature 608, 80–86; 2022). Pending business-case approval, UK Research and Innovation — the government’s main research-funding body — intends to award £38 million (US$44 million) to the Natural Environment Research Council to create a digitally enabled research infrastructure for building resilience against such catastrophes (go.nature.com/3cw1mfn).
Competing Interests
The authors declare no competing interests. More

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Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.This is a summary of: Li, X. et al. Climate change threatens terrestrial water storage over the Tibetan Plateau. Nat. Clim. Change https://doi.org/10.1038/s41558-022-01443-0 (2022). More

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