News items, either Eurbanlab related or general news about sustainable urban development.

Polar bears lose weight as climate bites

To survive, polar bears need to gain weight, not lose it. With a longer summer and less sea ice, it’s a lot harder to do that.

LONDON, 2 February, 2018 – Polar bears may be having a harder time than anybody thought. Biologists who monitored the hunting habits of the Arctic’s iconic predator found that bears have a faster metabolism – that is, they need high-energy foods more often – and are likely to lose weight just when they should be getting fat and ready for the winter.

Ursus maritimus is famous for going without food for long periods and then making up for it when the going is good. And for a polar bear, the going only gets good when there is a lot of sea ice and rich pickings among the seal population.

But US Geological Survey scientists who fitted monitors and video cameras to nine female polar bears for periods of 8 to 11 days and then tracked them on the ice of the Beaufort Sea, north of Alaska, report that five of their “volunteers” had lost weight.

Four of them had lost 10% of their body mass: that is, they could not catch seals often enough to put on weight. One had even lost muscle tissue.

The study confirms that bears are vulnerable to climate change. Sea ice minimum levels are falling at the rate of 14% a decade in the Arctic, and polar bears have been feeling the loss.

“Polar bears actually have much higher energy demands than predicted. They need to be catching a lot of seals”

But because the bear is a sit-and-wait predator, hunting ringed seals or bearded seals for preference as they haul out onto the ice, biologists had assumed that a resting bear would have a low metabolic rate. Not so, according to a new study in the journal Science.

The bears are active about one third of the time and use energy swimming and walking. The tests and observations were made during the period from April to July when bears catch most of their prey to store up the body fat they need.

In fact the instrument readings and tests of urine and blood samples told the scientists that the metabolic rate of a bear was more than 50% above previous calculations.

So a female seal out on the ice in the polar spring would need to eat one adult ringed seal, or three subadults, or 19 newborn seal pups, every 10 or 12 days just to stay as she was, at the same bodyweight.

Fall explained

But to succeed and breed in the winter, a female would ideally need to consume so much seal blubber that her fat levels matched her lean body mass. In April on the Beaufort Sea between 2014 and 2016, the bears in the test study had no great luck.

“We found that polar bears actually have much higher energy demands than predicted. They need to be catching a lot of seals,” said Anthony Pagano, a doctoral researcher from the University of California Santa Cruz, and a wildlife biologist with the US Geological Survey, who led the research.

Bear population in the Beaufort Sea has fallen by about 40% in the last decade. Now, biologists are beginning to see why.

“We now have the technology to learn how they are moving on the ice, their activity patterns and their energy needs, so we can better understand the implications of these changes we are seeing on the sea ice,” he said. – Climate News Network

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Climate effects strike US military bases

Climate effects strike US military installations today, a Pentagon study finds, despite White House failure to recognise any threat.

LONDON, 1 February, 2018 – Once more, the administration of President Trump seems puzzled about how seriously – if at all – it should regard how climate effects strike US military abilities.

In December the president listed the global threats he reckoned the US was facing – and climate change didn’t get a mention. Now, though, the US Department of Defense says many of its bases are feeling the worrying impacts of – climate change.

Around half of US military bases worldwide are already experiencing those impacts, a Pentagon report says. A survey shows risks to military infrastructure related to climate and extreme weather are widespread, affecting nearly 50% of the 1,684 sites involved.

The survey, described as a vulnerability assessment, identifies several key categories of risk: flooding, both from storm surges and causes such as rain, snow, ice and river overflows; extreme heat and cold; wind; drought; and wildfire. The Pentagon says the risks are not confined to vulnerable coastal sites.

Worrying picture

The survey paints what the Center for Climate & Security (CCS), a US non-partisan policy institute composed of security and military experts, calls “a concerning picture of current climate change-related risks to military installations both at home and abroad”.

John Conger, a senior policy adviser at the CCS, is a former US deputy under-secretary of defense. He told the Climate News Network:

“This report represents the first survey of climate impacts across the Department of Defense’s installation enterprise, and while it does not detail specific impacts, the breadth of impacts it reports is significant.

“No region is immune from climate impacts. This work will form the foundation of vulnerability assessments and mitigation planning in the future.”

“What is potentially significant about this survey … is how widespread climate change-related risks to military assets already are”

As rapid climate change is projected to intensify most of these risks during this century, the CCS says, it is reasonable to expect that military sites will become more vulnerable unless significant resources are devoted to adaptation, or the rate and scale of climate change are reduced.

“What is potentially significant about this survey … is how widespread climate change-related risks to military assets already are”, it says.

The vulnerability statement insists that the Pentagon will do what it thinks necessary to protect its bases: “Our warfighters require bases from which to deploy, on which to train, or to live when they are not deployed.

“If extreme weather makes our critical facilities unusable or necessitates costly or manpower-intensive work-arounds, that is an unacceptable impact.”

Present danger

The CCS says the survey makes it clear that climate change is already affecting the US military’s ability to do its job, finding that many installations are “highly vulnerable to a variety of different types of extreme or severe weather events.  Scientists expect heat waves, flooding, drought and wildfires to all increase over the coming decades.”

On the president’s December failure to include climate change in his list of global security threats to the US, Mr Conger said: “While it is unfortunate that mention of climate was dropped from the strategy, it isn’t surprising.

“I expect the US military will continue to focus on mission assurance efforts and it clearly recognises climate change is one of the risks it must consider.  The omission won’t block the DoD from working on climate resilience, but its reduction in priority is likely to slow progress.” – Climate News Network

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New risk of atmospheric aerosols as sunscreen

Using atmospheric aerosols to cut global warming is agreed to be risky. It might be even riskier to start it and then stop.

LONDON, 31 January, 2018 – Geoengineering, spraying atmospheric aerosols as the technofix answer to a warming planet, has been repeatedly denounced as dangerous by many critics. Now scientists say it could hide another hazard: once started, it might be dangerous to stop.

That is because their research shows that if this planetary sunscreen worked, and the technology was then brought to a halt, global warming would resume, at up to 10 times the speed.

And that would present even more danger for plants and animals already at risk from climate change, according to US scientists who write in the journal Nature Ecology and Evolution.

“Rapid warming after stopping would be a huge threat to the natural environment and biodiversity,” said Alan Robock, a climate scientist at Rutgers University – New Brunswick.

Huge risk

“If geoengineering ever stopped abruptly, it would be devastating, so you would have to be sure that it could be stopped gradually, and it is easy to think of scenarios that would prevent that.

“Imagine large droughts or floods around the world that could be blamed on geoengineering, and demands that it stop. Can we ever risk that?”

Almost all climate scientists argue that the proper way to control climate change is to drastically cut fossil fuel use and switch to wind, solar and water power to drive modern economies.

Even proponents of the technofix – the use of expensive technologies to screen or reflect sunlight by, for instance, spraying sulphate aerosols into the stratosphere – concede that prevention is best.

“If geoengineering ever stopped abruptly, it would be devastating, so you would have to be sure that it could be stopped gradually”

The geoengineering argument remains on the table of possibilities because, for the moment, progress towards real reduction is slow, and researchers have repeatedly warned that hopes of containing global warming, and limiting climate change, are dwindling.

So, once again, Rutgers scientists looked at ways of darkening the upper skies, and their implications. Although researchers have warned again and again of the dangers of such steps, at least one study has conceded that, in theory, the technology could be made to work.

So Professor Robock and colleagues considered the sky-spray solution again. They modelled the injection by high-flying aircraft of five million tons of sulphur dioxide into the upper atmosphere, over the equator, from 2020 to 2070. This is the annual equivalent of about one quarter of the sulphate aerosols hurled into the upper atmosphere by the eruption of Mt Pinatubo, in 1991, in the Philippines.

The sulphate clouds would spread evenly over the northern and southern hemispheres, to lower global temperatures by about 1°C, and bring them back down to the global average before the Industrial Revolution. But any halt in the programme would bring global warming back much faster than if geoengineering had never been deployed.

Long adaptation

The researchers then tried to calculate how plants and animals, all of which have adapted over the millennia to particular levels of rainfall and temperature, would respond. In many cases, the rate of warming would be four to seven times faster than the rate at which arthropods, birds, fish, mammals and reptiles could respond.

Climate change is already a threat to global biodiversity. Accelerated climate change after a period of containment would be even more dramatic.

“In many cases, you’d have to go one direction to find the same temperature but in a different direction to find the same precipitation. Plants, of course, can’t move reasonably at all. Some animals can move and some can’t,” said Professor Robock.

“We really need to look in a lot more detail at the impact on specific organisms and how they might adapt if geoengineering stops suddenly.” – Climate News Network

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Modest warming will raise Europe’s flood risk

Central and western Europe can expect a substantially higher flood risk in the future, even with ambitious cuts in temperature.

LONDON, 30 January, 2018 – If you live in Europe, get ready not only for a warmer future, but for a decidedly wetter one as well – with the likelihood in many regions of more disruption and danger, as the flood risk rises sharply.

Much of the continent is expected to see a steep rise in flood risk in coming years, even under an optimistic climate change scenario of 1.5°C of warming compared with pre-industrial levels.

A study by the European Commission’s Joint Research Centre (JRC)  assesses the flood impacts for three scenarios – of 1.5°C, 2°C and 3°C warming.

It finds, elaborating the tenor of numerous previous studies, that many risks are growing. Most of central and western Europe will experience a substantial increase in flood risk at all warming levels: the higher the warming, the higher the risk.

The global treaty on tackling climate change, the 2015 Paris Agreement, set 2°C as the maximum tolerable increase in global average temperatures above their pre-industrial level, while urging countries to aim for the much more demanding 1.5°C. How realistic even the 2°C target may prove is hotly debated.

A considerable increase in risk is predicted, even under the most optimistic scenario

Damage from floods across Europe is projected to more than double, from a 113% average increase if warming is kept to 1.5°C, to 145% under the 3°C scenario. In terms of population affected, the projected increase ranges from 86% to 123%.

While the pattern for central and western Europe is one of a consistent increase in flood risk, the study also finds that the risk may actually decrease with warmer temperatures in some parts of eastern Europe, although those results also show a high degree of uncertainty.

Similarly, in Spain, Portugal and Greece, the initial increase in impacts at 1.5°C turns into more uncertain projections for higher warming levels, because of a substantial reduction in annual rainfall.

The JRC analysis, published in the open access journal Climate,  improves scientists’ understanding of future trends in river flood risk in Europe, as well as stressing the need to prepare effective adaptation plans for a probable increase in the severity and frequency of European floods.

Finding the cause

The study authors’ aim was to identify consistent trends, independent of the models used, in flood risk in Europe attributable to climate change, and to identify the reasons for both the differences and the similarities between projections of river flood risk.

The three studies cover a wide range of methods and climate-relevant datasets (including for example temperature and precipitation), hydrological and flood modelling, and impact assessment.

The comparison sheds light on the influence of the data applied and methods used to assess impact projections. Results from the three assessments confirm that climate projections are the main driver influencing future flood risk trends.

The scientists say other factors, such as correcting any bias in climate projections, the method for assessing the year of exceeding global warming levels, and the spatial resolution of the input data did influence the results, but only to a small degree, and without affecting the direction of the projected changes in the three scenarios.

Reliability essential

They also point out the importance of using accurate modelling of the extent of floods to achieve reliable impact estimates. At the moment, this is limited by the availability of high-resolution digital elevation models (DEMs – digital representations of ground surfaces) over large areas, where small-scale features can considerably influence the distribution of floodwaters.

The study confirms that global warming has a significant impact on river flood risk in Europe, though it can vary in magnitude from region to region.

Even if global warming is limited to the levels spelt out in the Paris Agreement, changes in regional temperatures (and therefore climate change impacts) can vary significantly from the global average.

The encouraging news is that the results of this study show that substantial worsening of flood risk can be avoided, by limiting global warming to lower temperature thresholds. But a considerable increase in risk is predicted, even under the most optimistic scenario. – Climate News Network

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Coral reefs face infection risk from plastic

Plastic flotsam provides a liferaft for deadly bacteria – and a way of colonising coral reefs with killer infections.

LONDON, 29 January, 2018 – Scientists have established yet another hazard from the millions of tons of plastic waste that tip into the sea: it delivers microbial infection to the world’s coral reefs.

When plastic pollutants snag on coral reefs, the likelihood of disease rises from 4% to 89%, they calculate. That is an increase in risk of more than twentyfold.

And the impact on the world’s reefs – already under increasing hazard from ocean acidification and from bleaching in extremes of heat – could be devastating.

“Plastic debris acts like a marine motor home for microbes,” said Joleah Lamb, a researcher at Cornell University in the US. She began gathering data while at James Cook University in Australia.

“Plastics make ideal vessels for colonising microscopic organisms that could trigger disease if they come into contact with corals.

“Our work shows that plastic pollution is killing corals. Our goal is to focus less on measuring things dying and more on finding solutions”

“Plastic items – commonly made of polypropylene, such as bottle caps and toothbrushes – have been shown to become heavily inhabited by bacteria. This is associated with the globally devastating group of coral diseases known as white syndromes.”

She and colleagues from the US, Canada, Australia, Myanmar, Thailand and Indonesia report in the journal Science that between 2011 and 2014 they surveyed 124,000 reef-building corals from 159 reefs in the Asia-Pacific region.

One third of the reefs surveyed were polluted with plastic waste, the highest in Indonesian waters, the lowest off the Australian coast.

They calculate that, right now, the number of plastic bags, cups, bottles, toothbrushes and bits of packaging snagged on the reefs in the region could be 11.1 billion. By 2025, there could be 15.7 bn plastic objects stuck on the same reefs.

No return

And, they report, the presence of plastic was associated with a 20-fold increase in risk of disease, and in particular infections know to marine biologists as skeletal eroding band disease, white syndrome and black band disease.

The items snagged on the corals deprived them of sunlight and oxygen, and weakened the coral to the point at which invasive pathogens could gain a hold.

“What’s troubling about coral disease is that once the coral tissue loss occurs, it’s not coming back,” Dr Lamb said. “It’s like getting gangrene on your foot and there is nothing you can do to stop it from affecting your whole body.”

The Asia-Pacific region is home to more than 55% of the world’s coral reefs. Complex reef structures – reefs with branching corals, for instance – were eight times more likely to trap floating plastic waste.

An estimated 12 billion metric tons of indestructible plastic waste is in the world’s landfills. Somewhere between 4.8 million and 12.7 million metric tons of plastic waste gets into the oceans in a single year.

Rich resource

Coral reefs are among the richest habitats on the planet: a diseased or dying reef can no longer provide food and shelter for a vast range of sea creatures.

Pollution and disease also put at risk much of the estimated $375bn value that reefs offer to 275 million people as sources of fisheries, tourism and coastal protection.

“Our work shows that plastic pollution is killing corals. Our goal is to focus less on measuring things dying and more on finding solutions,” said Drew Harvell, professor of ecology and evolutionary biology at Cornell, and one of the authors.

“While we can’t stop the huge impact of global warming on coral health in the short term, this new work should drive policy toward reducing plastic pollution.” – Climate News Network

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Doomsday Clock puts world risk at 65-year high

The Doomsday Clock, a measure by scientists of the risk to global survival, now says the danger is the greatest since 1953.

LONDON, 26 January, 2018 – The Doomsday Clock, which judges the threat to world peace and the environment, has advanced significantly, with nuclear weapons and climate change held largely responsible.

The Bulletin of the Atomic Scientists has moved the symbolic Clock forward by 30 seconds, to two minutes to midnight, reflecting the scientists’ view of the main global dangers. They say much of the blame rests with the administration of President Donald Trump.

The only other time the clock, revised annually, has been set so close to catastrophe was 65 iears ago, in 1953, after the US and the Soviet Union exploded their first thermonuclear bombs.

Rachel Bronson, the bulletin’s president and CEO, said in a statement: “Major nuclear actors are on the cusp of a new arms race, one that will be very expensive and will increase the likelihood of accidents and misperceptions.

Weapons more usable

“Across the globe, nuclear weapons are poised to become more rather than less usable because of nations’ investments in their nuclear arsenals.”

The Center for Climate & Security (CCS) is a US non-partisan policy institute of security and military experts. In November 2017 it said climate change and nuclear threats are closely linked and must be tackled together.

The bulletin’s authors, from its science and security board, say they are disturbed by the rising tensions on the Korean peninsula, the increasing emphasis and expenditure on nuclear weapons by major powers, the absence of arms control negotiations around the world, and the wavering political will to combat climate change.

They repeatedly single out the Trump administration as a major factor behind the increased risks, citing what they describe as the president’s volatility; the inconsistency of the administration’s foreign policy; and its apparent disdain for science, including senior appointments of climate change deniers.

“The White House office of science and technology policy is essentially not staffed. The official mechanisms to tie public policy to reality are currently absent”

One board member, Sharon Squassoni, of George Washington University’s Institute for International Science and Technology Policy, said Russia was also responsible for raising tensions, for example by deploying ground-launched cruise missiles in 2017 in breach of the 1987 Intermediate-range Nuclear Forces (INF) treaty.

Some experts argue that a comparison with the height of the cold war exaggerates the current dangers, and not all agree that the global risks of nuclear weapons are as severe now as they were then. Vipin Narang, of the Massachusetts Institute of Technology, tweeted: “Today, the risk of single use may be higher, but it’s unlikely to threaten global destruction.”

On climate change, the bulletin scientists say it is worsening: after flattening out for some years, global greenhouse gas emissions have resumed their rise, and the levels of the polar ice caps are at new lows.

They say the administration is making “an insufficient response” to climate change and is turning its back on reality: “In its rush to dismantle rational climate and energy policy, the administration has ignored scientific fact and well-founded economic analyses.

Heartening response

“Here in the US, the incoming President Trump promptly appointed a cadre of avowed climate denialists and quickly started reversing existing climate measures,” said Sivan Kartha, a senior scientist at the Stockholm Environmental Institute. But he was encouraged by the global response to Mr Trump’s actions.

Thankfully, Dr Kartha said, the White House had met “a reassuring and affirming resistance…Other countries reaffirmed their commitment to climate action. And within the United States, there’s been this huge We Are Still In movement of states, cities, business, faith-based communities, reaffirming their commitment to climate action and global cooperation.”

President Trump was also criticised for downgrading the science in his administration. Lawrence Krauss, the chair of the bulletin’s board of sponsors, said that 2017 was the first year since the position was created more than half a century ago with no presidential science adviser.

“The White House office of science and technology policy is essentially not staffed,” Krauss said. “The official mechanisms to tie public policy to reality are currently absent.” – Climate News Network

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Water scarcity threat to India and South Africa

More than a third of India’s electricity supply is at risk from water scarcity, which also threatens urban life in parts of South Africa.

LONDON, 23 January, 2018 – Water scarcity is now a real threat in two developing countries at the forefront of efforts to reduce climate change, India and South Africa.

This is not the tragically familiar story of extreme weather, stunted crops and foreshortened lives. It is a different sort of threat: to urban life, to industrial development, and to attempts to end poverty.

More than 80% of India’s electricity comes from thermal power stations, burning coal, oil, gas and nuclear fuel. Now researchers from the US-based World Resources Institute, after analysing all of India’s 400+ thermal power plants, report that its power supply is increasingly in jeopardy from water shortages.

The researchers found that 90% of these thermal power plants are cooled by freshwater, and nearly 40% of them experience high water stress. The plants are increasingly vulnerable, while India remains committed to providing electricity to every household by 2019.

Between 2015 and 2050 the Indian power sector’s share of national water consumption is projected to grow from 1.4 to nine per cent, and by 2030, 70% of the country’s thermal power plants are likely to experience increased competition for water from agriculture, industry and municipalities.

Power sector choking

“Water shortages shut down power plants across India every year,” said O P Agarwal of WRI India. “When power plants rely on water sourced from scarce regions, they put electricity generation at risk and leave less water for cities, farms and families. Without urgent action, water will become a chokepoint for India’s power sector.”

Between 2013 and 2016 14 of India’s 20 largest thermal utility companies experienced one or more shutdowns because of water shortages. WRI calculates that shutdowns cost these companies over INR 91 billion ($1.4 billion) in potential revenue from the sale of power.

It says water shortages cancelled out more than 20% of the country’s growth in electricity generation in 2015 and 2016.

The report offers solutions, including notably a move towards solar and wind energy. India already has a target for 40% of its power to come from renewables by 2030, under the Paris Agreement on climate change.

“Renewable energy is a viable solution to India’s water-energy crisis,” said Deepak Krishnan, co-author of the report. “Solar PV and wind power can thrive in the same water-stressed areas where thermal plants struggle…”

A policy brief produced by WRI and the International Renewable Energy Agency details ways for India’s power sector to reduce water usage and carbon emissions by 2030.

“The challenge exceeds anything a major city has had to face anywhere in the world since the Second World War or 9/ll”

In Africa the dangers of water scarcity for one of the continent’s best-known cities, Cape Town, are imminent and, some believe, almost apocalyptic.

The city faces the prospect within three months of becoming the world’s first major city to run out of water, al-Jazeera reports.

It says the city’s water supplies are now so low that in late April it will declare “Day Zero”, the day when its reservoirs fall below a combined capacity of 13.5%.

This will mean Cape Town turning off the taps, except in the poorest neighbourhoods, and installing around 200 water collection sites across the city.

Water usage in the Western Cape province, which includes Cape Town,  is now limited to a daily ration of 87 litres per person. If Day Zero dawns, that will drop to about 25 litres. The World Health Organisation says about 20 litres should be enough “to take care of basic hygiene needs and basic food hygiene”.

Rains start later

The province has had three years of drought. Kevin Winter, a senior lecturer in environmental science at the University of Cape Town, told al-Jazeera that as a winter rainfall region, people would normally expect rainfall to start somewhere around April.

“But that’s no longer the case, it comes a whole lot later at the end of June, or in early July, if we are lucky,” he said. “We are experiencing a rapid change in our weather patterns, which is increasingly evident of a climate change…”

Bridgetti Lim Bandi, who has lived in the city all her life, said Cape Town’s rainfall pattern had changed dramatically within the last two decades. “We don’t have a traditional Cape Town winter any more,” she told al-Jazeera.

Helen Zille is premier of the Western Cape province. She wrote on 22 January in the Daily Maverick: “The question that dominates my waking hours now is: When Day Zero arrives‚ how do we make water accessible and prevent anarchy?

“And if there is any chance of still preventing it‚ what is it we can do? …the challenge exceeds anything a major city has had to face anywhere in the world since the Second World War or 9/ll.” – Climate News Network

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Urban forests add to cities’ health and wealth

Planting more urban forests is a simple way not only to improve the health of a city’s people, but to make them wealthier too.

LONDON, 22 January, 2018 – Climate scientists who calculated the value of urban forests to the world’s great cities have now worked out how town planners can almost double their money. Just plant 20% more trees.

More than half the world now lives in cities, and one person in 10 lives in a megacity: one that is home to at least 10 million people.

The trees that shade the parks and gardens and line the urban streets – London planes, limes, magnolias, pines and so on – are known to add to property values and to make living conditions better for millions who must endure the increasing heat extremes of the urban world.

Last year researchers put a value on the contributions of the urban forest: $500 million to the average megacity, they calculated, in pollution absorbed, temperatures lowered and moisture taken up.

More needed

Now Theodore Endreny, professor of environmental resources engineering at the State University of New York, and colleagues from Parthenope University in Naples, Italy, report in the journal Ecological Modelling that there is more to be done.

Tree canopies already cover 20% of the area of their 10 sample megacities in five continents. They looked at their models of tree cover, human population, air pollution, energy use, climate and spending power and found room for improvement: the same cities could find room for 20% more forest.

“By cultivating the trees within the city, residents and visitors get direct benefits,” Professor Endreny said. “They’re getting an immediate cleansing of the air that’s around them.

“They’re getting that direct cooling from the trees, and even food and other products. There’s potential to increase the coverage of urban forests in our megacities, and that would make them more sustainable, better places to live.”

“While nature provides a bounty of essential goods and services, such as food, flood protection and many more, it also has rich social, cultural, spiritual and religious significance”

Cities are afflicted by the notorious heat island effect, and climate scientists have repeatedly warned that extremes of heat and humidity could rise to potentially lethal levels in many of the world’s great cities.

The latest study is part of a wider shift in approach by urban planners and civic authorities to seek ways to mitigate the climate change driven by ever more profligate consumption of fossil fuels, without actually adding to this consumption by installing ever more air conditioning plant.

And on the same day, a second team of scientists emphasised the same conclusion: work with nature to confront climate change and improve the lives of people in the developing world, put at risk by climate change driven in part by the despoliation of the forests and the degradation of the land.

They argue in the journal Science that a better understanding of the way nature – in the form of forests, wetlands, savannahs and all the creatures that depend on the natural world – underwrites human wellbeing should inform political and economic decisions.

Local knowledge

In many cases, this would involve attending to the wisdom and experience of local communities and indigenous people who depend more directly on nature’s riches.

“Nature’s contributions to people are of critical importance to rich and poor in developed and developing countries alike. Nature underpins every person’s wellbeing and ambitions – from health and happiness to prosperity and security.

“People need to better understand the full value of nature to ensure its protection and sustainable use,” said Sir Robert Watson, chair of the Intergovernmental Platform on Biodiversity and Ecosystem Services.

“This new inclusive framework demonstrates that while nature provides a bounty of essential goods and services, such as food, flood protection and many more, it also has rich social, cultural, spiritual and religious significance – which needs to be valued in policymaking as well.” – Climate News Network

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By air, land and sea, global warming rises

Global warming took surface temperatures in 2017 to near-record levels, while the upper oceans reached their hottest known level.

LONDON, 19 January, 2018 – Global warming is real, and it’s happening now. Within hours of the announcement by scientists in the US that 2017 was at least the third warmest year recorded, if not the second, over the Earth’s land and oceans, there comes a further revelation: 2017 was also the warmest year on record for the global oceans.

Both disclosures are consistent with what scientists had expected from climate change, driven by global warming as a consequence of the profligate combustion of fossil fuels that dump ever greater levels of greenhouse gases in the atmosphere.

But they add to the scientists’ sense of urgency at the need for rapid and radical action to cut greenhouse emissions. Of the US announcement, Dr Dann Mitchell, of the University of Bristol, UK, said: “The most recent global temperature observations are in line with what we expected, both from our underlying theory, but also our model projections and understanding of the climate system.

“The atmosphere is warming, by almost 1°C globally to date, and we are getting ever closer to the Paris Agreement target of 1.5°C which we are so desperately trying to avoid.”

The news that the oceans are continuing to warm to hitherto unknown levels comes in an updated ocean analysis from the Institute of Atmospheric Physics/Chinese Academy of Science (IAP/CAS). Its study was published as an early online release in the journal Advances in Atmospheric Sciences.

“The biggest natural influence on the climate is being dwarfed by human activities – predominantly CO₂ emissions”

The authors say that in 2017 the oceans in the upper 2000-metre layer of water were warmer than the second warmest year, 2015, and above the 1981-2010 climatological reference period.

Thanks to their large heat capacity, the oceans absorb warming caused by human activities, and more than 90% of the Earth’s extra heat from global warming is absorbed by them.

The study says the global ocean heat content record robustly represents the signature of global warming, and is affected less by weather-related “noise” and climate variability such as El Niño and La Niña events.

The IAP says the last five years have been the five warmest years in the oceans, as the long-term warming trend driven by human activities continued unabated.

The rise in ocean heat in 2017 occurred in most regions of the world. Increases in ocean temperature cause the volume of seawater to expand, contributing to the global average sea level rise, which in 2017 amounted to 1.7 mm. Other consequences include a decline in ocean oxygen, the bleaching of coral reefs, and the melting of sea ice and ice shelves.

Discrepancy explained

The globally averaged temperature over land and ocean surfaces for 2017 was the third highest since record keeping began in 1880, according to NOAA scientists.

There is a slight difference in the figures for 2017’s temperature. NOAA says the globally averaged temperature for the year makes it the third hottest since record-keeping began in 1880, while NASA says in a separate analysis that 2017 was the second warmest on record, behind 2016.

This minor difference is explained by the different methods used by the two agencies to analyse global temperatures, they say, though they point out that over the long term their records agree closely.

Both agree that the five warmest years on record have all occurred since 2010. The UK Met Office and the World Meteorological Organisation (WMO) also listed 2017 among the top three warmest years on record.

One striking feature of the consensus on 2017’s place in the record books is less about what did happen, and more about what didn’t. Last year was the second or third hottest after 2016, and on a level with 2015, the data show.

No boost

But those two years were affected by El Niño, the periodic natural phenomenon in the Pacific, which helps to boost temperatures worldwide. 2017 was not an El Niño year.

If it had been, the researchers say, it would probably have been the warmest year yet, outstripping the heat in 2015 and 2016.

The acting director of the UK Met Office, Professor Peter Stott, told BBC News: “It’s extraordinary that temperatures in 2017 have been so high when there’s no El Niño. In fact, we’ve been going into cooler La Niña conditions.

“It shows clearly that the biggest natural influence on the climate is being dwarfed by human activities – predominantly CO₂ emissions.”

The WMO secretary-general, Petteri Taalas, said the long-term temperature trend was far more important than the ranking of individual years: “That trend is an upward one. Seventeen of the 18 warmest years on record have all been during this century, and the degree of warming during the past three years has been exceptional.

“Arctic warmth has been especially pronounced, and this will have profound and long-lasting repercussions on sea levels, and on weather patterns in other parts of the world.” – Climate News Network

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Aquatic life is at risk as carbon levels rise

Marine and freshwater fish could one day be in trouble as ever-rising levels of carbon dioxide affect aquatic life.

LONDON, 18 January, 2018 – New studies warn that global warming is not good news for aquatic life, putting at risk the creatures both of the seas and of inland waterways.

Experiments in Australia confirm that increased temperatures driven by ever-rising atmospheric levels of the greenhouse gas carbon dioxide reduce the flow of energy up the marine food web, which would be bad news for the ocean’s top predators – and some prized fish catches.

Another study finds that ever-greater levels of dissolved carbon dioxide in rivers and lakes could disrupt the dietary supply for creatures higher in the food chain.

Scientists have been warning for years that global warming and ever-increasing levels of acidification could harm ocean productivity. Researchers from the University of Adelaide report in the Public Library of Science journal PLOS Biology that they put the proposition directly to the test.

“Healthy food webs are important for the maintenance of species diversity and provide a source of income and food for millions of people worldwide”

They built 12 huge laboratory aquaria with water temperatures and acidity levels that matched predictions of climate change, and then introduced a range of sea creatures: algae, shrimp, sponges, snails, fishes and so on.

They found that the plants flourished, largely in the form of cyanobacteria, or blue-green algae. “This increased primary productivity does not support food webs, however, because these cyanobacteria are largely unpalatable, and they are not consumed by herbivores,” said Hadayet Ullah, who led the study.

“Healthy food webs are important for the maintenance of species diversity and provide a source of income and food for millions of people worldwide. Therefore, it is important to understand how climate change is altering marine food webs in the near future.”

Alarm, too, about the impact on freshwater species is not new. German biologists had access to data collected every month at four river dams from 1981 to 2015. They report in the journal Current Biology that acidification levels in the reservoirs had steadily increased in that time.

Fleas vulnerable

So they tested the response of species of daphnia, the water flea – and a source of food for other freshwater creatures – to changing water chemistry. The higher the acidity, the weaker the response of the water fleas to the scent of nearby predators.

“Many freshwater organisms rely on their sense of smell. If that sense is compromised in other species due to rising CO2 levels this development might have far-reaching consequences for the entire ecosystem,” said Linda Weiss of the Ruhr University of Bochum, who led the study.

“Follow-up studies must now be carried out, in order to determine if the acidification of freshwater systems is a global phenomenon and in what way other species react to rising CO2 levels.” – Climate News Network

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