China Has Surprised the World With Climate Action Announcement
By Hao Tan, Elizabeth Thurbon, John Mathews, Sung-Young Kim
China's President Xi Jinping surprised the global community recently by committing his country to net-zero emissions by 2060. Prior to this announcement, the prospect of becoming "carbon neutral" barely rated a mention in China's national policies.
China currently accounts for about 28% of global carbon emissions – double the U.S. contribution and three times the European Union's. Meeting the pledge will demand a deep transition of not just China's energy system, but its entire economy.
Importantly, China's use of coal, oil and gas must be slashed, and its industrial production stripped of emissions. This will affect demand for Australia's exports in coming decades.
It remains to be seen whether China's climate promise is genuine, or simply a ploy to win international favor. But it puts pressure on many other nations – not least Australia – to follow.
Goodbye, Fossil Fuels
Coal is currently used to generate about 60% of China's electricity. Coal must be phased out for China to meet its climate target, unless technologies such as carbon-capture and storage become commercially viable.
Natural gas is increasingly used in China for heating and transport, as an alternative to coal and petrol. To achieve carbon neutrality, China must dramatically reduce its gas use.
Electric vehicles and hydrogen fuel-cell vehicles must also come to dominate road transport - currently they account for less than 2% of the total fleet.
China must also slash the production of carbon-intensive steel, cement and chemicals, unless they can be powered by renewable electricity or zero-emissions hydrogen. One report suggests meeting the target will mean most of China's steel is produced using recycled steel, in a process powered by renewable electricity.
Modeling in that report suggests China's use of iron ore – and the coking coal required to process it into steel – will decrease by 75%. The implications for Australia's mining industry would be huge; around 80% of our iron ore is exported to China.
It is critically important for Australian industries and policymakers to assess the seriousness of China's pledge and the likelihood it will be delivered. Investment plans for large mining projects should then be reconsidered accordingly.
Conversely, China's path towards a carbon neutral economy may open up new export opportunities for Australia, such as "green" hydrogen.
A Renewables Revolution
Solar and wind currently account for 10% of China's total power generation. For China to meet the net-zero goal, renewable energy generation would have to ramp up dramatically. This is needed for two reasons: to replace the lost coal-fired power capacity, and to provide the larger electricity needs of transport and heavy industry.
Two factors are likely to reduce energy demand in China in coming years. First, energy efficiency in the building, transport and manufacturing sectors is likely to improve. Second, the economy is moving away from energy- and pollution-intensive production, towards an economy based on services and digital technologies.
It's in China's interests to take greater action on climate change. Developing renewable energy helps China build new "green" export industries, secure its energy supplies and improve air and water quality.
The Global Picture
It's worth considering what factors may have motivated China's announcement, beyond the desire to do good for the climate.
In recent years, China has been viewed with increasing hostility on the world stage, especially by Western nations. Some commentators have suggested China's climate pledge is a bid to improve its global image.
The pledge also gives China the high ground over a major antagonist, the US, which under President Donald Trump has walked away from its international obligations on climate action. China's pledge follows similar ones by the European Union, New Zealand, California and others. It sets an example for other developing nations to follow, and puts pressure on Australia to do the same.
The European Union has also been urging China to take stronger climate action. The fact Xi made the net-zero pledge at a United Nations meeting suggests it was largely targeted at an international, rather than Chinese, audience.
However, the international community will judge China's pledge on how quickly it can implement specific, measurable short- and mid-term targets for net-zero emissions, and whether it has the policies in place to ensure the goal is delivered by 2060.
Much is resting on China's next Five Year Plan – a policy blueprint created every five years to steer the economy towards various priorities. The latest plan, covering 2021–25, is being developed. It will be examined closely for measures such as phasing out coal and more ambitious targets for renewables.
Also key is whether the recent rebound of China's carbon emissions – following a fall from 2013 to 2016 – can be reversed.
The 2060 commitment is bold, but China may look to leave itself wriggle room in several ways.
First, Xi declared in his speech that China will "aim to" achieve carbon neutrality, leaving open the option his nation may not meet the target.
Second, the Paris Agreement states that developed nations should provide financial resources and technological support to help developing countries reduce their emissions. China may make its delivery of the pledge conditional on this support.
Third, China may seek to game the way carbon neutrality is measured – for example, by insisting it excludes carbon emissions "embodied" in imports and exports. This move is quite likely, given exports account for a significant share of China's total greenhouse gas emissions.
So for the time being, the world is holding its applause for China's commitment to carbon neutrality. Like every nation, China will be judged not on its climate promises, but on its delivery.
Hao Tan is an Associate professor, University of Newcastle.
Elizabeth Thurbon is a Scientia Fellow and Associate Professor in International Relations / International Political Economy, UNSW.
John Mathews is a Professor Emeritus, Macquarie Business School, Macquarie University.
Sung-Young Kim is a Senior Lecturer in International Relations, Discipline of Politics & International Relations, Macquarie School of Social Sciences, Macquarie University.
Hao Tan receives funding from the Australia Research Council (ARC) Discovery Project 2019-2021. He previously received funding from the Academy of the Social Sciences in Australia, and funding from the Confucius Institute Headquarters under the "Understanding China Fellowship" in 2017.
Elizabeth Thurbon currently receives funding from the Australian Research Council (ARC) and the Academy of Korean Studies. She has previously received funding from the Academy of Social Sciences in Australia and the Korea Foundation. She is an elected member of the Executive Council of the Society for the Advancement of Socio-Economics (SASE) and a Research Committee member and Board member of the Jubilee Australia Research Centre (JARC).
John Mathews receives funding from the ARC for the study of the clean energy transition in East Asia.
Sung-Young Kim receives funding from the Australia Research Council (ARC) and has previously received funding from the Academy of Korean Studies (AKS). He is Chair of the Organising Committee for the 2021 Australian Political Studies Association (APSA) Annual Conference and is Treasurer of the Korean Studies Association of Australasia (KSAA).
Reposted with permission from The Conversation.
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By Suresh Dhaniyala and Byron Erath
A fast-spreading variant of the coronavirus that causes COVID-19 has been found in at least 10 states, and people are wondering: How do I protect myself now?
Airborne Particles Are Still the Biggest Problem<p>The <a href="https://theconversation.com/why-it-matters-that-the-coronavirus-is-changing-and-what-this-means-for-vaccine-effectiveness-152383" target="_blank" rel="noopener noreferrer">SARS-CoV-2 variants</a> are believed to spread primarily through the air rather than on surfaces.</p><p>When someone with the coronavirus in their respiratory tract coughs, talks, sings or even just breathes, infectious respiratory droplets can be expelled into the air. These droplets are tiny, predominantly in the range of <a href="https://www.sciencedirect.com/science/article/pii/S0021850211001200?casa_token=KtyrsEfbeqcAAAAA:vv10sSxm33tzg0EQvNMIFtV7GCu5gE9QAzuyzHKr2_4Cl0OFkUJoGwzn4d0ZnEWS19NsOTuH" target="_blank" rel="noopener noreferrer">1-100 micrometers</a>. For comparison, a human hair is about 70 micrometers in diameter.</p><p>The larger droplets fall to the ground quickly, rarely traveling farther than 6 feet from the source. The bigger problem for disease transmission is the tiniest droplets – those less than 10 micrometers in diameter – which can remain suspended in the air as aerosols for <a href="https://academic.oup.com/cid/article/50/5/693/325466" target="_blank">hours at a time</a>.</p>
<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="bb67b83dcafe589f350daf3df60fa29d"><iframe lazy-loadable="true" src="https://www.youtube.com/embed/UNCNM7AZPFg?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span>
What Can You Do to Stay Safe?<p>1) Pay attention to the type of face mask you use, and how it fits.</p><p>Most off-the-shelf face coverings are not 100% effective at preventing droplet emission. With the new variant spreading more easily and likely infectious at lower concentrations, it's important to select coverings with materials that are most effective at stopping droplet spread.</p><p>When available, N95 and surgical masks consistently perform the best. Otherwise, face coverings that use <a href="https://www.sciencedirect.com/science/article/pii/S2352431620301802?casa_token=-Dj6nGBAm24AAAAA:qq9BpbzCKaPDFcV73ohA2fCnhE_Zlkss6Bei3kUwq9QYndhHj0Vafbbd-ef_855lx6knDfUt" target="_blank">multiple layers of material</a> are preferable. Ideally, the material should be a tight weave. High thread count cotton sheets are an example. Proper fit is also crucial, as gaps around the nose and mouth can <a href="https://pubs.acs.org/doi/10.1021/acsnano.0c03252" target="_blank" rel="noopener noreferrer">decrease the effectiveness by 50%</a>.</p><p>2) Follow social distancing guidelines.</p><p>While the current social distancing guidelines are not perfect – <a href="https://theconversation.com/what-a-smoky-bar-can-teach-us-about-the-6-foot-rule-during-the-covid-19-pandemic-145517" target="_blank" rel="noopener noreferrer">6 feet isn't always enough</a> – they do offer a useful starting point. Because aerosol concentrations levels and infectivity are highest in the space immediately surrounding anyone with the virus, increasing physical distancing can help reduce risk. Remember that people are infectious <a href="https://medical.mit.edu/faqs/COVID-19#faq-10" target="_blank" rel="noopener noreferrer">before they start showing symptoms</a>, and they many never show symptoms, so don't count on seeing signs of illness.</p><p>3) Think carefully about the environment when entering an enclosed area, both the ventilation and how people interact.</p><p>Limiting the size of gatherings helps reduce the potential for exposure. Controlling indoor environments in other ways can also be a highly effective strategy for reducing risk. This includes <a href="https://theconversation.com/what-a-smoky-bar-can-teach-us-about-the-6-foot-rule-during-the-covid-19-pandemic-145517" target="_blank" rel="noopener noreferrer">increasing ventilation rates</a> to bring in <a href="https://theconversation.com/keeping-indoor-air-clean-can-reduce-the-chance-of-spreading-coronavirus-149512" target="_blank" rel="noopener noreferrer">fresh air and filtering existing air</a> to dilute aerosol concentrations.</p><p>On a personal level, it is helpful to pay attention to the types of interactions that are taking place. For example, many individuals shouting can create a higher risk than one individual speaking. In all cases, it's important to minimize the amount of time spent indoors with others.</p><p>The CDC has warned that B.1.1.7 could <a href="https://www.cdc.gov/mmwr/volumes/70/wr/mm7003e2.htm?s_cid=mm7003e2_w" target="_blank" rel="noopener noreferrer">become the dominant SARS-CoV-2 variant</a> in the U.S. by March. Other fast-spreading variants have also been found in <a href="https://virological.org/t/genomic-characterisation-of-an-emergent-sars-cov-2-lineage-in-manaus-preliminary-findings/586" target="_blank" rel="noopener noreferrer">Brazil</a> and <a href="https://www.who.int/csr/don/31-december-2020-sars-cov2-variants/en/" target="_blank" rel="noopener noreferrer">South Africa</a>. Increased vigilance and complying with health guidelines should continue to be of highest priority.</p>
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By Tara Lohan
A key part of the United States' clean energy transition has started to take shape, but you may need to squint to see it. About 2,000 wind turbines could be built far offshore, in federal waters off the Atlantic Coast, in the next 10 years. And more are expected.
Threats to Birds<p>One of the gravest threats facing birds is climate change, according to Audubon, which found that rising temperatures threaten <a href="https://www.audubon.org/2019climateissue" target="_blank" rel="noopener noreferrer">nearly two-thirds of North America's bird species</a>. That's why the impending development of offshore wind is a good thing, says Shilo Felton, a field manager in the organization's Clean Energy Initiative, but it also comes with dangers to birds that need to be better studied and mitigated.</p><p>The most obvious risk comes from birds colliding with spinning turbine blades. But offshore wind developments can also displace birds from foraging or roost sites, as well as migratory pathways.</p><p>Along the Atlantic Coast four imperiled species are of top concern to conservationists: the endangered piping plover, red knot, roseate tern and black-capped petrel, which is being considered for listing under the Endangered Species Act.</p><p>"Those four species are of utmost importance to make sure that we understand the impacts," says Felton. "But beyond that there are many species that are protected under the Migratory Bird Treaty Act and the Fish and Wildlife Conservation Act that could potentially see more impacts from offshore wind."</p><p>Northern gannets, for example, are at risk not just for collision but <a href="https://www.researchgate.net/publication/308703197_Possible_impacts_of_offshore_wind_farms_on_seabirds_a_pilot_study_in_Northern_Gannets_in_the_southern_North_Sea" target="_blank">habitat displacement</a>.</p>
A northern gannet flying along Cape May, N.J. Ann Marie Morrison / CC BY-NC-ND 2.0<p>"There's <a href="https://www.sciencedirect.com/science/article/abs/pii/S0006320716303196" target="_blank">some evidence</a> that they just won't use areas where turbines are, but that also excludes them from key foraging areas," says Felton. Researchers are still studying what this may mean for the birds. But a <a href="https://www.sciencedirect.com/science/article/pii/S0141113620305304" target="_blank">study</a> published in December 2020 conducted at Bass Rock, Scotland — home to the world's largest northern gannet colony — found that wind developments could reduce their growth rate, though not enough to cause a population decline.</p><p>Other birds, such as great cormorants and European shags, are <a href="https://www.sciencedirect.com/science/article/abs/pii/S0006320716303196" target="_blank">attracted to wind developments</a> and use the infrastructure to rest while opening up new foraging areas farther from shore.</p><p>"There's plenty of potential for a bird to use a wind farm and still to avoid the turbines themselves," says Felton.</p><p>Birds like pelicans, however, are less versatile in their movements and are at particular risk of collision because of their flight pattern, she says.</p><p>But how disruptive or dangerous offshore turbines will be along the East Coast isn't yet known.</p><p>Federal and state agencies, along with nongovernmental organizations, says Felton, have done good research to try to better understand those potential impacts. "But these are all theoretical, because we don't have a lot of offshore wind yet in the United States."</p>
Threats to Ocean Life<p>Birds aren't the only wildlife of concern. More development in ocean waters could affect a litany of marine species, some of which are already facing other pressures from overfishing, pollution, habitat destruction and climate change.</p><p>Scientists have found that marine mammals like whales and dolphins could be disturbed by the jarring sounds of construction, especially if pile driving is used to hammer the steel turbine platform into the seafloor.</p><p>The noises, though short-lived, could impede communication between animals, divert them from migration routes or cause them to seek less suitable areas for feeding or breeding. Research from Europe found that harbor porpoises, seals and dolphins may avoid development areas during construction. In most, but <a href="https://iopscience.iop.org/article/10.1088/1748-9326/7/4/045101" target="_blank">not all cases</a>, the animals were believed to have returned to the area following construction.</p><p>The biggest concern for conservation groups in the United States is the critically endangered North American right whale. There are fewer than 400 remaining, and the species' habitat overlaps with a number of planned wind development areas along the East Coast.</p><p>"Offshore wind is in no way the cause of the challenges the whales face, but it's going to be another pressure point," says John Rogers, senior energy analyst for the Union of Concerned Scientists.</p><p>Researchers aren't sure how right whales will respond to the noise from pile driving.</p><p>"But we are concerned, based on what we know about how whales react to other noise sources, that they may avoid [wind development] areas," says Kershaw.</p><p>And if that displacement causes them to miss out on important food resources, it could be dangerous for a species already on the brink.</p><p>There are a few other potential threats, too.</p><p>Ships associated with the development — more plentiful during construction — also pose a danger. In the past few years cargo ships, fishing boats and other vessels have caused half of all deaths of North Atlantic right whales.</p>
A juvenile right whale breaches against the backdrop of a ship near the St. Johns River entrance. Florida Fish and Wildlife Conservation Commission / NOAA Research Permit #775-1600-10<p>And after construction, the noise from the spinning turbines will be present in the water at low decibels. "We don't quite know how the great whales will react to those sounds," says Jeremy Firestone, the director of the Center for Research in Wind at the University of Delaware.</p><p>Other marine mammals may also perceive the noise, but at low decibels it's unlikely to be an impediment, <a href="http://www.int-res.com/abstracts/meps/v309/p279-295/" target="_blank">research has found</a>.</p><p>And it's possible that wind development could help some ocean life. Turbine foundations can attract fish and invertebrates for whom hard substrates create habitat complexity — known as the "reef effect," according to researchers from the University of Rhode Island's <a href="https://dosits.org/animals/effects-of-sound/anthropogenic-sources/wind-turbine/" target="_blank" rel="noopener noreferrer">Discovery of Sound in the Sea</a> program. Exclusion of commercial fishing nearby may also help shelter fish and protect marine mammals from entanglements in fishing gear.</p>
Ensuring Safe Development<p>Despite the potential dangers, researchers have gathered a few best practices to help diminish and possibly eliminate some risks.</p><p>When it comes to ship strikes, the easiest thing is to slow boats down, mandating a speed of <a href="https://biologicaldiversity.org/w/news/press-releases/vessel-speed-limits-sought-protect-endangered-north-atlantic-right-whales-2020-08-06/" target="_blank">10 knots</a> in wind development areas, and using visual and acoustic monitoring for whales.</p><p>Adjusting operations to reduce boat trips between the shore and the wind development will also help. A new series of service operating vessels can allow maintenance staff to spent multiple days onsite, says Kershaw, cutting down on boat traffic.</p><p>For construction noise concerns, developers can avoid pile driving during times of the year when whales are present. And, depending on the marine environment, developers could use "quiet foundations" that don't require pile driving. These include gravity-based or suction caisson platforms.</p><p>Floating turbines are also used in deep water, where they're effectively anchored in place — although that poses its own potential danger. "We have concerns that marine debris could potentially become entangled around the mooring cables of the floating arrays and pose a secondarily entanglement risk to some species," says Felton, who thinks more research should be conducted before those become operational in U.S. waters — a process that's already underway in Maine, where a <a href="https://composites.umaine.edu/2020/08/05/diamond-offshore-wind-rwe-renewables-join-the-university-of-maine-to-lead-development-of-maine-floating-offshore-wind-demonstration-project/" target="_blank" rel="noopener noreferrer">demonstration project is being built</a>.</p><p>If loud noises are unavoidable during construction, noise-reducing technologies such as bubble curtains can help dampen the sound. And scheduling adjacent projects to conduct similar work at the same time could limit the duration of disturbances.</p>
The foundation installation of the off shore wind farm Sandbank using a bubble curtain. Vattenfall / Ulrich Wirrwa / CC BY-NC-ND 2.0<p>Once turbines become operational, reducing the amount of light on wind platforms or using flashing lights could help deter some seabirds, NRDC <a href="https://www.nrdc.org/sites/default/files/harnessing-wind-advance-wind-power-offshore-ib.pdf" target="_blank" rel="noopener noreferrer">researchers reported</a>. And scientists are exploring using ultrasonic noises and ultraviolet lighting to keep bats away. "Feathering," or shutting down the turbine blades during key migration times, could also help prevent fatalities.</p><p>"We need to make sure that offshore wind is the best steward it can be of the marine ecosystem, because we want and expect it to be a significant part of the clean energy picture in some parts of the country," says Rogers. "We also have to recognize that we're going to learn by doing, and that some of these things we're going to figure out best once we have more turbines in the water."</p><p>That's why environmental groups say it's important to establish baseline information on species before projects begin, and then require developers to conduct monitoring during construction and for years after projects are operational.</p><p>Employing an "adaptive management framework" will ensure that developers can adjust their management practices as they go when new information becomes available, and that those best practices are incorporated into the requirements for future projects.</p>
Putting Research Into Action<p>Advancing these conversations at the federal level during the Trump administration, though, has been slow going.</p><p>"We didn't really have any productive discussions with the administration in the last four years," says Kershaw.</p><p>And when it comes to birds, Felton says the Bureau of Ocean Energy Management's recently completed "draft cumulative environmental impact statement" covering offshore wind developments had a lot of good environmental research, but little focus on birds.</p><p>"Part of that comes from the current administration's interpretation of the Migratory Bird Treaty Act," she says.</p><p>President Trump has been hostile to both wind energy <em>and</em> birds, <a href="https://www.nytimes.com/2021/01/05/climate/trump-migratory-bird-protections.html" target="_blank">and finished gutting the Migratory Bird Treaty Act</a> in his administration's the final days, removing penalties for companies whose operations kill migratory birds.</p><p>There's hope that the Biden administration will take a different approach. But where the federal government has been lacking lately, Kershaw says, they've seen states step up.</p><p>New York, for example, has established an <a href="https://www.nyetwg.com/" target="_blank" rel="noopener noreferrer">Environmental Technical Working Group</a> composed of stakeholders to advise on environmentally responsible development of offshore wind.</p><p>The group is led by the New York State Energy Research and Development Authority, but it isn't limited to the Empire State. It's regional in focus and includes representatives from wind developers with leases between Massachusetts and North Carolina; state agencies from Massachusetts to Virginia; federal agencies; and science-based environmental NGOs.</p><p>New York's latest solicitation for clean energy projects includes up to 2,500 megawatts of offshore wind and <a href="https://www.nyetwg.com/announcements" target="_blank" rel="noopener noreferrer">requires developers</a> to contribute at least $10,000 per megawatt for regional monitoring of fisheries and other wildlife.</p><p>Environmental groups have also worked directly with developers, including an agreement with Vineyard Wind — an 800-megawatt project off the Massachusetts coast that could be the first utility-scale wind development in federal waters — to help protect North Atlantic right whales.</p><p>The agreement includes no pile driving from Jan. 1 to April 30, ceasing activities at other times when whales are visually or acoustically identified in the area, speed restrictions on vessels, and the use of noise reduction technology, such as a bubble curtain during pile driving.</p><p>"The developers signed the agreement with us, and then they incorporated, most, if not all of those measures into the federal permitting documents," says Kershaw. "The developers really did a lot of bottom up work to make sure that they were being very protective of right whales."</p><p>Environmental groups are in talks with other developers on agreements too, but Felton wants to see best practices being mandated at the federal level.</p><p>"It's the sort of a role that should be being played by the federal government, and without that it makes the permitting and regulation process less stable and less transparent," she says." And that in turn slows down the build out of projects, which is also bad for birds because it doesn't help us address and mitigate for climate change."</p><p>Kershaw agrees there's a lot more work to be done, especially at the federal level, but thinks we're moving in the right direction.</p><p>"I think the work that's been done so far in the United States has really laid the groundwork for advancing this in the right way and in a way that's protective of species and the environment," she says. "At the same time, it's important that offshore wind does advance quickly. We really need it to help us combat the worst effects of climate change."</p><p><em><a href="https://therevelator.org/author/taralohan/" target="_blank" rel="noopener noreferrer">Tara Lohan</a> is deputy editor of The Revelator and has worked for more than a decade as a digital editor and environmental journalist focused on the intersections of energy, water and climate. Her work has been published by The Nation, American Prospect, High Country News, Grist, Pacific Standard and others. She is the editor of two books on the global water crisis.</em></p><p><em style="">Reposted with permission from <a href="https://therevelator.org/offshore-wind-wildlife" target="_blank" style="">The Revelator</a>. </em></p>
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By Frank La Sorte and Kyle Horton
Millions of birds travel between their breeding and wintering grounds during spring and autumn migration, creating one of the greatest spectacles of the natural world. These journeys often span incredible distances. For example, the Blackpoll warbler, which weighs less than half an ounce, may travel up to 1,500 miles between its nesting grounds in Canada and its wintering grounds in the Caribbean and South America.
Blackpoll warbler. PJTurgeon / Wikipedia<p>We used this information to determine how the number of migratory bird species varies based on each city's level of <a href="https://www.britannica.com/science/light-pollution" target="_blank" rel="noopener noreferrer">light pollution</a> – brightening of the night sky caused by artificial light sources, such as buildings and streetlights. We also explored how species numbers vary based on the quantity of tree canopy cover and impervious surface, such as concrete and asphalt, within each city. Our findings show that cities can help migrating birds by planting more trees and reducing light pollution, especially during spring and autumn migration.</p>
Declining Bird Populations<p>Urban areas contain numerous dangers for migratory birds. The biggest threat is the risk of <a href="https://doi.org/10.1650/CONDOR-13-090.1" target="_blank">colliding with buildings or communication towers</a>. Many migratory bird populations have <a href="http://dx.doi.org/10.1126/science.aaw1313" target="_blank">declined over the past 50 years</a>, and it is possible that light pollution from cities is contributing to these losses.</p><p>Scientists widely agree that light pollution can <a href="https://doi.org/10.1073/pnas.1708574114" target="_blank">severely disorient migratory birds</a> and make it hard for them to navigate. Studies have shown that birds will cluster around brightly lit structures, much like insects flying around a porch light at night. Cities are the <a href="https://doi.org/10.1002/fee.2029" target="_blank" rel="noopener noreferrer">primary source of light pollution for migratory birds</a>, and these species tend to be more abundant within cities <a href="https://onlinelibrary.wiley.com/doi/abs/10.1111/gcb.13792" target="_blank" rel="noopener noreferrer">during migration</a>, especially in <a href="https://doi.org/10.1016/j.landurbplan.2020.103892" target="_blank" rel="noopener noreferrer">city parks</a>.</p>
Composite image of the continental U.S. at night from satellite photos. NASA Earth Observatory images by Joshua Stevens, using Suomi NPP VIIRS data from Miguel Román, NASA's Goddard Space Flight Center