Greenland’s undercut glaciers melting faster than thought

A press release from NASA: Greenland's glaciers flowing into the ocean are grounded deeper below sea level than previously measured, allowing intruding ocean water to badly undercut the glacier faces. That process will raise sea levels around the world much faster than currently estimated, according to a team of researchers led by Eric Rignot of the University of California, Irvine (UCI), and NASA's Jet Propulsion Laboratory, Pasadena, California.

The researchers battled rough waters and an onslaught of icebergs for three summers to map the remote channels below Greenland's marine-terminating glaciers for the first time. Their results have been accepted for publication in the journal Geophysical Research Letters and are now available online.

"Measurements are challenging to obtain beneath hundreds of meters of seawater in poorly charted, ice-infested fjords," Rignot wrote. He and co-authors Ian Fenty of JPL, Cilan Cai and Yun Xu of UCI, and Chris Kemp of Terrasond Ltd., Seattle, obtained and analyzed around-the-clock measurements of the depth, salinity and temperature of channel waters and their intersection with the coastal edge of Greenland's ice sheet.

The team found some glaciers perched on giant earthen sills, protecting them from the punishing salt waters for now, while others were being severely eroded out of sight beneath the surface, meaning they could collapse and melt much sooner.  "Numerical ice sheet models do not take into account these interactions and as a result underestimate how fast the glaciers will respond to climate warming," said Rignot....

Glaciologists from the University of California, Irvine, and JPL mapped remote Greenland fjords by ship in 2014. Their findings show that Greenland's glaciers are likely to be melting faster than previously thought. Credits: UCI/Maria Stenzel

Experts push climate-proof cities, coastal communities

Imelda V. Abano at InterAksyon.com: Experts meeting here say climate-proofing a city or coastline is urgently needed to protect millions of people and key infrastructure. From Manila to New York, cities and coastal areas across the globe are increasingly vulnerable to the impacts of climate change coupled with population growth and poverty.

The adaptations prompted by climate change are meant to minimize risks from extreme weather events, powerful storm surges, sea level rise, droughts, rising temperatures and other effects of a changing climate.

Urban populations, according to the United Nations, is projected to increase from 3.9 billion in 2014 to 6.3 billion in 2050. Asia, the most climate-vulnerable region despite its lower level of urbanization, is home to 53 percent of the world's urban population, followed by Europe with 14 percent and Latin America and the Caribbean with 13 percent.

Smart planning of cities and coastal areas, such as building or planning defenses, securing water supplies or moving people to higher ground, is essential to prepare for the climatic forces, said Steven Wade, head of the Scientific Consultancy at the Met Office, a United Kingdom-based national weather service.

Wade, who presented climate model outputs for climate adaptation in cities at the World Engineers Summit (WES) organized by the Institution of Engineers Singapore, said that adaptation of cities is a significant challenge for planners and engineers, particularly in cities with ageing infrastructure, rapid growth and vulnerable coastal locations....

An aerial night view of Marina Bay, Singapore, shot by Nicolas Lannuzel., Wikimedia Commons via Flickr, under the Creative Commons Attribution-Share Alike 2.0 Generic license

Mangroves help protect coastal areas against sea level rise

Blue & Green Tomorrow: Mangrove forests could play a crucial role in protecting coastal areas from sea level rise caused by climate change, according to new research involving the University of Southampton. A joint study between researchers at the University of Southampton along with colleagues from the Universities of Auckland and Waikato in New Zealand used leading-edge mathematical simulations to study how mangrove forests respond to elevated sea levels.

Taking New Zealand mangrove data as the basis of a new modelling system, the team were able to predict what will happen to different types of estuaries and river deltas when sea levels rise. They found areas without mangroves are likely to widen from erosion and more water will encroach inwards, whereas mangrove regions prevent this effect – which is likely due to soil building up around their mesh-like roots and acting to reduce energy from waves and tidal currents.

Coastal estuaries and recesses in coastlines that form bays receive the run-off from erosion on steep catchments, which give them the tendency to fill in over time. As they infill, the movement of the tidal currents over the shallow areas create networks of sandbanks and channels. The sand banks grow upward to keep pace with water-level changes, while the channels get deeper to efficiently drain the excess water out to sea.

The researchers’ latest work shows that mangroves can facilitate this process, by adding leaf and root structures into the accumulating sediment, which increase the elevation while enhancing the trapping of new sediment arriving from the catchment.

Dr Barend van Maanen from the University of Southampton explains: “As a mangrove forest begins to develop, the creation of a network of channels is relatively fast. Tidal currents, sediment transport and mangroves significantly modify the estuarine environment, creating a dense channel network. Within the mangrove forest, these channels become shallower through organic matter from the trees, reduced sediment resuspensions (caused by the mangroves) and sediment trapping (also caused by the mangroves) and the sea bed begins to rise, with bed elevation increasing a few millimetres per year until the area is no longer inundated by the tide.”...

Mangroves in Zanzibar, shot by Fanny Schertzer, Wikimedia Commons, under the Creative Commons Attribution-Share Alike 3.0 Unported license

As sea level rise accelerates, buying shorefront property becomes a game of musical chairs

Ivy Main at the Energy Collective: Thank God for climate change deniers. They may eventually be the only buyers for shorefront real estate.

Sea level rise may not cause widespread flooding until later in this century or into the next one, but real estate deals involve long timelines: the useful life of a new house or a commercial building can be at least fifty years, while an infrastructure project might last a hundred years or more.

And of course, it’s one thing to lose your house, and another to lose the ground beneath it. Sea level rise means low-lying real estate now comes with an expiration date.

So smart buyers—and landowners—have to consider not just today’s flood maps, but also ones that haven’t been drawn yet. If a rising sea will threaten property some decades from now, it will depreciate over time, like a car. At some point only chumps and climate deniers will buy.

Head-in-the-sand posturing still dominates the headlines, like Florida Governor Rick Scott’s alleged ban on the use of the term “climate change,” or the North Carolina legislature’s silly (and costly) attempt to legislate sea level rise out of existence. Now the Federal Emergency Management Agency (FEMA) hopes to force states to get serious about climate change by requiring states to do a better job planning for natural disasters caused in part by global warming. FEMA’s goal is to save money through better planning, but conservatives have attacked the requirement as politically motivated....

FEMA photo of beach houses in Pensecola, Florida, damaged by Hurricane Ivan in 2004

Rapid coastal population growth may leave many exposed to sea-level rise

Science Daily: The number of people potentially exposed to future sea level rise and associated storm surge flooding may be highest in low-elevation coastal zones in Asia and Africa, according to new projections published March 11, 2015 in the open-access journal PLOS ONE by Barbara Neumann from Kiel University, Germany, and colleagues.

Many coastal areas are densely populated and exposed to a range of coastal hazards, including sea level rise. As coastal population density and urbanization continue to increase, researchers are investigating how coastal populations may be affected by potential environmental impacts at global and regional scales in the future. Based on four different sea-level and socioeconomic scenarios, the authors of this study assessed future population changes by the years 2030 and 2060 in the low-elevation coastal zone and estimated trends in exposure to 100-year coastal floods.

From the scenario-based projections, the researchers estimated that the number of people living in the low-elevation coastal zone, as well as the number of people exposed to flooding from 100-year storm surge events, was highest in Asia
. China, India, Bangladesh, Indonesia, and Viet Nam had the largest numbers of coastal population per country and accounted for more than half of the total number of people living in low-elevation coastal zones, both now and in the future scenarios. However, Africa was estimated to experience the highest future rates of population growth and urbanization in the coastal zone, particularly in Egypt and sub-Saharan countries in West and East Africa. While the authors' research method does not explicitly consider possible population displacement or out-migration due to factors such as sea level rise, the results highlight countries and regions with a high degree of potential exposure to coastal flooding, and also help to identify regions where policies and adaptive planning for building resilient coastal communities are essential....

NASA image of Haiphong

Malaysia moves against coastal erosion crisis

Sohail Rahman in Al-Jazeera.com: ...Malaysia and Denmark ... have been working on environmental projects for over a decade. Both recognise the importance of their coastline and Denmark has years of experience in dealing with water levels and rising seas.

...So fast forward to Penang, coastal erosion and fresh water fishermen. They have a huge problem of coastal degradation. Is global warming the reason for the way typhoons have hit Asia Pacific these past few years, or the terrible floods that hit Malaysia in December 2014?

It could be a factor if the bigger global environmental jigsaw puzzle is worked out Here, though, the government, local and national is working with local nongovernmental organisations, acknowledging there is a need to support the livelihoods of over 200 fisherman on the island that locals call Pulau Pinang.

Together they identify vulnerable areas, work out which of the 150 species of hmangrove will be best suited to binding the land, grow quickly and feed the natural wildlife that depends on the plants. Keeping salt water away and encouraging freshwater wildlife that can sustain communities, such as fish, prawns and lobster to return.

...It is working yet we hear very little about it. Some NGOs such as The Consumer Association of Penang say the government need to do more and quickly. It is an easy statement to make but no government official likes to be told what to do. Yet Malaysia will be doing that soon enough. Telling its neighbours or the international community at the UN what they think and what needs to be done....

Pakistan's coastal villagers retreat as seas gobble land

Rina Saeed Khan in Reuters via the Thomson Reuters Foundation: For fisherman Sammar Dablo, it was as if "the seawater stole our homes" when land erosion forced his village to relocate further inland on Pakistan's south coast.

The people of the fan-shaped Indus Delta, where the Indus River meets the Arabian Sea, are among the poorest of the poor, mostly illiterate and living in wooden shacks on the mud flats. As seawater has washed into the delta, destroying thousands of hectares of fertile land and contaminating underground water channels, they survive by fishing in the saltwater creeks where dolphins are a common sight.

...The move was not easy, as households had to spend 15,000 rupees ($149) each to build new huts for themselves, he added. The story of Phirt village is not an isolated case. According to Dablo, many other communities in the delta are also shifting as their land disappears.

The latest scientific report from the Intergovernmental Panel on Climate Change pointed out that at the same time as sea levels are rising, most Asian deltas are sinking due to groundwater extraction, floodplain engineering and the trapping of sediment by dams.

The Indus Delta has seen an 80 percent reduction in sediment since the early 20th century, according to a 2009 paper published in Nature Geoscience. Around 20 dams and a large number of canals divert the waters of the Indus River, depriving the delta of fresh water.

Some inhabitants have moved to inland mud flats, where they do not have to buy the land they occupy. Others are decamping to Karachi’s coastal villages where relatives have settled. ... Climate change is clearly increasing vulnerabilities in the delta area. Sea-level rise is contributing to higher storm surges, erosion, flooding and salinity, according to WWF-Pakistan...

NASA view of the Indus River delta

NOAA establishes ‘tipping points’ for sea level rise related flooding

A press release from NOAA: By 2050, a majority of U.S. coastal areas are likely to be threatened by 30 or more days of flooding each year due to dramatically accelerating impacts from sea level rise, according to a new NOAA study, published today in the American Geophysical Union’s online peer-reviewed journal Earth’s Future.

The findings appear in the paper From the Extreme to the Mean: Acceleration and Tipping Points for Coastal Inundation due to Sea Level Rise, and follows the earlier study, Sea Level Rise and Nuisance Flood Frequency Changes around the United States, by the report’s co-author, William Sweet, Ph.D., oceanographer at NOAA’s Center for Operational Oceanographic Products and Services (CO-OPS). The new analysis was presented at a news conference today at the annual AGU fall meeting in San Francisco.

NOAA scientists Sweet and Joseph Park established a frequency-based benchmark for what they call “tipping points,” when so-called nuisance flooding, defined by NOAA’s National Weather Service as between one to two feet above local high tide, occurs more than 30 or more times a year.

Based on that standard, the NOAA team found that these tipping points will be met or exceeded by 2050 at most of the U.S. coastal areas studied, regardless of sea level rise likely to occur this century. In their study, Sweet and Park used a 1½ to 4 foot set of recent projections for global sea level rise by year 2100 similar to the rise projections of the Intergovernmental Panel for Climate Change, but also accounting for local factors such as the settlement of land, known as subsidence.

These regional tipping points will be surpassed in the coming decades in areas with more frequent storms, the report said. These tipping points will be also be exceeded in areas where local sea levels rise more than the global projection of one and half to four feet. This also includes coastal areas like Louisiana where subsidence, which is not a result of by climate change, is causing land to sink below sea level....

FEMA image from 2005, Houston evacuating from Hurricane Rita

Mumbai, Kolkata most vulnerable to climate change

The Financial Express (India): India’s populous coastal cities Mumbai and Kolkata are most vulnerable to loss of life and properties due to coastal flooding in the second half of the century, the government has said quoting a UN report ahead of a key global climate conference in Peruvian capital Lima.

The UN’s Intergovernmental Panel on Climate Change (IPCC) has warned against extreme weather events like occurrence of heatwave, heavy precipitation, droughts, floods, cyclones and wildfire that cause damage to ecosystems and human systems in various regions, Environment Minister Prakash Javadekar said.

“… India is among the top 20 countries and regions most at risk based on analysis of climate risk and coping ability. Mumbai and Kolkata will have the greatest population and assets exposure to coastal flooding in 2070,” he said.

The minister’s statement assumes significance at a time when representatives of governments are scheduled to meet in Lima from tomorrow for the Climate Change Conference to lay the foundation for an effective, new and universal climate change agreement in Paris in 2015.

Mumbai' sea-face at night

Sea level rise won’t only affect infrastructure

Scoop via Forest & Bird (New Zealand): The independent conservation organisation Forest & Bird is asking the Parliamentary Commissioner for the Environment (PCE) to widen the focus of her next report on climate change-driven sea level rise.

A preliminary report on sea level rise was released by the PCE today. The PCE will release another report next year on the impacts of sea level rise on the most vulnerable areas of coastline around the country, and the risks to infrastructure in those areas.

Forest & Bird Group Manager Campaigns and Advocacy Kevin Hackwell says the next report should also take into account the impacts of sea level rise on our natural coastal ecosystems, and recommend the best ways to deal with sea level rise.

He says some critical natural features could be changed forever by sea level rise. “For example the huge Kaipara Harbour north of Auckland covers 947 square kilometres at high tide, with nearly half of that area exposed as mudflats and sandflats at low tide,” Kevin Hackwell says.

...“Quite a few of our shore birds breed just above the current high tide level on our open coasts or at the head of estuaries. For instance the four remaining nesting sites of New Zealand’s Seabird of the Year, the fairy tern, could be wiped out by storm surges,” Kevin Hackwell says.

“We would also like to see the PCE make recommendations on how sea level rise should be dealt with. Building extensive sea walls is likely to be very expensive, in many places unrealistic, and in the long run may create more problems than they would solve....

Sphinx Rock in Marie's Leg Cove, New Zealand, shot by Pseudopanax, Wikimedia Commons, under the Creative Commons 3.0 license 

US east coast cities face frequent flooding due to climate change

Suzanne Goldenberg in the Guardian (UK): Dozens of America’s east coast cities face routine tidal flooding under climate change, researchers said on Wednesday. Miami – where the habitues of South Beach are used to sloshing through water at high tide – will deploy new pumps this week to hold back the waters of the King Tides, the highest annual high tides, which are projected to crest at 3.5 feet (1.07m).

Other cities are going to have to undertake similar measures if they want to avoid soggy streets in the future, the researchers said.

The report, Encroaching Tides: How Sea Level Rise and Tidal Flooding Threaten U.S. East and Gulf Coast Communities over the Next 30 Years, from the Union of Concerned Scientists (UCS), found most of the towns on America’s east coast will see triple the number of flooding events by 2030.

By 2045, those towns will see 10 times as many tidal floods – and those floods will seep further inland, and last longer, the researchers said. Many coastal towns already see dozens of small tidal floods every year, typically lasting only a few hours.

But the frequency of such events is marching upwards because of sea level rise – which at some points along the east coast is more than twice the global average. Some east coast towns have recorded four times as many flood days as in 1970, the report found.....

Flood and wind damage at the US Naval Academy in Annapolis, from Hurricane Isabel in 2003. US Navy photo

Study finds Great Barrier Reef is an effective wave absorber

University of Southampton News Release: New research has found that the Great Barrier Reef, as a whole, is a remarkably effective wave absorber, despite large gaps between the reefs. This means that landward of the reefs, waves are mostly related to local winds rather than offshore wave conditions.

As waves break and reduce in height over reefs, this drives currents that are very important for the transport of nutrients and larvae. This reduction in wave height also has implications for shoreline stability. Transition

The Great Barrier Reef in Australia is the largest coral reef system in the world, extending 2,300 km alongshore. The reef matrix is a porous structure consisting of thousands of individual reefs, with gaps in between. The porosity varies in that is it much lower in the north where the continental shelf is narrow and there is extensive reef flats; and is greater in the south where the shelf reaches up to 300 km wide and there are extensive lagoons.

Previously, there have been several studies investigating how individual reefs in the Great Barrier Reef influence ocean waves. However, this was the first, comprehensive, large-scale study of the influence of an entire offshore reef system on ocean wave transmission. The researchers used a 16-year record of satellite altimeter measurements of wave heights.

The team was led by Dr Shari Gallop, Research Fellow in Geology and Geophysics at the University of Southampton, and included Dr Ivan Haigh, also from the University of Southampton; Professor Ian Young, Vice-Chancellor of the Australian National University (ANU); Professor Roshanka Ranasinghe, Professor of Climate Change Impacts and Coastal Risk (UNESCO-IHE, Deltares, ANU), and Dr Tom Durrant (Bureau of Meteorology, Australia).

The aim was to see how wave height reduction is influenced by the porosity of the reef matrix, sea level and wind speed. Dr Gallop says: “There was no evidence that in less porous areas wave heights are lessened. This is because individual reefs, like islands, cast a ‘wave shadow’ over a large area, so that a matrix of individual reefs is remarkably efficient at reducing waves.” ....

The Great Barrier Reef, shot by Sarah Ackerman, Wikimedia Commons via Flickr, under the Creative Commons 2.0 license

View on Private Sector: Insuring against climate change

Aamna Modhin in SciDev.net: A recent UN report said that global warming will cause trillions of dollars of damage to coral reefs in the Caribbean. It also warned that small island states will be disproportionally affected by the impact of climate change: their coral reefs, which their economies depend on, are under significant environmental stress.

One news report on the document noted that the insurance industry could play a role in safeguarding such nations’ economies by providing stronger theoretical frameworks in which to understand risks to reefs.

I asked Mike Maran, chief science officer at insurance firm Catlin Group, what such efforts might look like. He tells me the firm is sponsoring a global scientific survey of coral reefs, including some in the Caribbean, with the aim of monitoring their health over the coming years.

Why would an insurance company do such a thing? Maran explains that scientific evidence helps insurers understand what might happen to reefs in the future, and how fast. Although firms do not insure the reefs directly, Maran says they have a broad obligation to study the risks society will face in the future so as to understand and manage those risks. The collection of robust scient
ific information gives insurers a good understanding of how the planet is changing and the impact these changes will have on policyholders.

Many of the risks involved in policies firms do provide — for example insurance for homes, other properties and businesses — could be linked to climate change, and so understanding changes to reefs as a proxy measure of that will help quantify those risks. For example, reef degradation could have an impact on fishing or tourism industries and so indirectly change the value of insured assets....

A coral reef in Biscayne National Park in Florida, shot by a Park Service employee

Managing coasts under threat from climate change and sea-level rise

EurekAlert via University of Southampton: Coastal regions under threat from climate change and sea-level rise need to tackle the more immediate threats of human-led and other non-climatic changes, according to a team of international scientists.

The team of 27 scientists from five continents, led by Dr Sally Brown at the University of Southampton, reviewed 24 years of Intergovernmental Panel on Climate Change (IPCC) assessments (the fifth and latest set being published in 2013 and 2014). They focused on climate change and sea-level rise impacts in the coastal zone, and examined ways of how to better manage and cope with climate change.

They found that to better understand climate change and its impacts, scientists need to adopt an integrated approach into how coasts are changing. This involves recognising other causes of change, such as population growth, economic development and changes in biodiversity. Dr Brown emphasised that: "Over the last two and half decades, our scientific understanding of climate change and sea-level rise, and how it will affect coastal zones has greatly increased. We now recognise that we need to analyse all parts of our human and natural environments to understand how climate change will affect the world."

The scientists also acknowledged that long-term adaptation to climate change can greatly reduce impacts, but further research and evaluation is required to realise the potential of adaptation. "Many parts of the coast can, with forward planning, adapt to sea-level rise, but we need to better understand environments that will struggle to adapt, such as developing countries with large low-lying river deltas sensitive to salinisation, or coral reefs and particularly small, remote islands or poorer communities," said Dr Brown.

...Dr Jochen Hinkel from Global Climate Forum in Germany, who is a co-author of this paper and a Lead Author of the coastal chapter for the 2014 IPCC Assessment Report added: "The IPCC has done a great job in bringing together knowledge on climate change, sea-level rise and is potential impacts but now needs to complement this work with a solution-oriented perspective focusing on overcoming barriers to adaptation, mobilising resources, empowering people and discovering opportunities for strengthening coastal resilience in the context of both climate change as well as existing coastal challenges and other issues."...

A 2011 winter storm battering Inverclyde, Scotland, shot by easylocum, Wikimedia Commons via Flickr, under the Creative Commons Attribution 2.0 Generic license 

Just right' plant growth may make river deltas resilient

A press release from Indiana University: Research by Indiana University geologists suggests that an intermediate amount of vegetation -- not too little and not too much -- is most effective at stabilizing freshwater river deltas. The study, "Optimum vegetation height and density for inorganic sedimentation in deltaic marshes," was published online Aug. 24 by Nature Geoscience. The findings may help guide restoration of river deltas, such as those near the mouth of the Mississippi River, which are under threat as sea levels rise.

Authors are William Nardin, a postdoctoral fellow in the Department of Geological Sciences in the IU Bloomington College of Arts and Sciences; and Douglas A. Edmonds, who holds the Robert R. Shrock Professorship in Sedimentary Geology and is an assistant professor of geological sciences.

Vegetation on marsh surfaces in river deltas can slow the flow of water and cause more sediment to be deposited, helping prevent sea-level rise from drowning sensitive marshlands. But the study finds that, if the vegetation is too tall or dense, it diverts water into the river channel, resulting in less sediment being deposited on the marsh.

“In river deltas the effect of vegetation on sedimentation seems to follow the Goldilocks principle,” Edmonds said. “You want the amount of vegetation that is just right -- not too much, but also not too little.”

The world’s river deltas are rich and productive and are home to about 10 percent of the world’s population. But they are threatened by an array of forces, including population growth, pollution, development and erosion, as well as sea-level rise associated with climate change.

...In tidal saltwater marshes, research has shown that vegetation enhances sedimentation. But scientists know less about how vegetation affects sedimentation in freshwater marshes that are common in river deltas. Nardin and Edmonds used sophisticated computer modeling to study how marsh vegetation influences the transport and deposition of sediment in river deltas. They conducted 75 simulations involving varying scenarios of vegetation height and density and rates of water flow.

They found that vegetation of intermediate height and density results in the greatest deposition of sand and mud. However, if the plants are too tall or densely packed, sediment tends to remain in the river channel, bypassing marshes and being carried directly to the sea....

From the IU website: This image shows freshwater marsh vegetation in Wax Lake Delta, La. Aquatic vegetation on low-elevation marshes is pictured in the foreground, while woody vegetation occupies a levee on the left. The open water in the distance is a deltaic distributary channel. Photo by Elizabeth Olliver

Study measures steep coastal costs of China's GDP growth

Seed Daily via SPX: A new study by a team of Chinese and American conservation biologists quantifies the serious consequences of China's recent economic growth on its coastal ecosystems. By several measures, 1978 was the beginning of a hugely successful surge in the nation's ability to produce economic value, but that surge brought accelerated degradation in the vitality of its coastal ecosystems.

The combined analysis of economic growth, human activities and impacts, and environmental quality data appears in the journal Scientific Reports. It shows that after reforms declared in 1978, which liberalized the Chinese economy to spur growth, many human economic activities with deleterious environmental impacts increased markedly, even in the absence of significant population growth.

The economic reforms led to a shift from an inland agrarian economy to an industrial economy concentrated on the coast. In lockstep with that shift came environmental problems such as declines in fish size and diversity, damage to coral reefs, and a surge in harmful algal blooms.

"This study flags the problem and screams out this is a problem that has to be dealt with," said Mark Bertness, professor of ecology and evolutionary biology at Brown University and the paper's second author. "This has all happened within a generation."

Lead author Qiang He of Beijing Normal University, who led the research while a visiting scholar in the Bertness lab at Brown, said the research shows that economic growth alone can generate environmental impacts. "We show that in a country with a relatively constant coastal population growth rate, economic growth rather than population growth is the major driver of coastal degradation, while previous science often addresses how increasing human population degrades the coastal and marine environment," He said....

Shanghai's Bund viewed from the Oriental Pearl Tower in Pudong, Shanghai, shot by Bobak, Wikimedia Commons, under the Creative Commons 2.5 license

NOAA analysis reveals significant land cover changes in US coastal regions

A press release from NOAA: A new NOAA nationwide analysis shows that between 1996 and 2011, 64,975 square miles in coastal regions -- can area larger than the state of Wisconsin -- experienced changes in land cover, including a decline in wetlands and forest cover with development a major contributing factor.

Overall, 8.2 percent of the nation’s ocean and Great Lakes coastal regions experienced these changes. In analysis of the five year period between 2001-2006, coastal areas accounted for 43 percent of all land cover change in the continental U.S. This report identifies a wide variety of land cover changes that can intensify climate change risks, such as loss of coastal barriers to sea level rise and storm surge, and includes environmental data that can help coastal managers improve community resilience.

"Land cover maps document what's happening on the ground. By showing how that land cover has changed over time, scientists can determine how these changes impact our plant’s environmental health," said Nate Herold, a NOAA physical scientist who directs the mapping effort at NOAA's Coastal Services Center in Charleston, South Carolina.

Among the significant changes were the loss of 1,536 square miles of wetlands, and a decline in total forest cover by 6.1 percent. The findings mirror similar changes in coastal wetland land cover loss reported in the November 2013 report, Status and Trends of Wetlands in the Coastal Watersheds of the Conterminous United States 2004 to 2009, an interagency supported analysis published by the U.S. Fish and Wildlife Service and NOAA.

...Development was a major contributing factor in the decline of both categories of land cover. Wetland loss due to development equals 642 square miles, a disappearance rate averaging 61 football fields lost daily. Forest changes overall totaled 27,515 square miles, equaling West Virginia, Rhode Island and Delaware combined. This total impact, however, was partially offset by reforestation growth. Still, the net forest cover loss was 16,483 square miles.

India risks loss of 8.7% of GDP by 2100 on climate change

The Economic Times via PTI (India): A global failure to respond to climate changes could result in about 8.7 per cent economic loss in India's Gross Domestic Product (GDP) by 2100, Asian Development Bank said today.  "India, one of the largest agrarian economies in the world, is deeply at risk from climate change, and could see economic losses of up to 8.7 per cent of its gross domestic product (GDP) by 2100 if the world fails to respond to a host of climate threats, the Manila bas
ed multi-lateral funding agency said in a report.

Report titled 'Assessing the Costs of Climate Change and Adaptation in South Asia' predicts Bangladesh, Bhutan, India, the Maldives, Nepal and Sri Lanka will see an average annual economic loss of 1.8 per cent of their collective GDP by 2050, rising sharply to 8.8 per cent by 2100.  "Without changes to current global behavior, India would see economic losses equivalent to 1.8 per cent of annual GDP by 2050, widening to 8.7 per cent by the end of the century."

But if mitigation and adaptation steps are taken to keep the temperature rise below 2 degrees Celsius, the damage could be kept below 2 per cent by 2100, it said.  "Agriculture provides employment and livelihood opportunities to most of India's rural population and changes in temperature and rainfall, and an increase in floods and droughts linked to climate change, would have a devastating impact on people's food security, incomes, and lives," said Bindu Lohani, ADB Vice-President for Knowledge Management and Sustainable Development.

Changes in rainfall patterns are likely to benefit rice output in most north-eastern states, however southern states could see annual yields decline by 5 per cent in 2030s, 14.5 per cent in 2050s, and 17 per cent in 2080s.

"The country has 8,000 km of coastline and nearly half the country's 28 states could face serious consequences from a rise in the sea level, with Gujarat expected to suffer the highest level of inundation, and Maharashtra the largest number of affected people," as per the report....

Eggplants for sale in Gujarat, shot by Arne Hückelheim, Wikimedia Commons, under the Creative Commons Attribution-Share Alike 3.0 Unported license 

The sinking mega-cities

A bulletin from Lloyd's: As sea levels rise, ground levels in coastal megacities are also falling – with potentially disastrous implications for insurers. Insurers of large property portfolios in the world’s great coastal cities will have factored the effects of climate change into their catastrophe models – including rising sea levels and more frequent storm surges. But what’s often missed is that many of these cities are sinking faster than the water is rising. In some, subsidence outstrips sea level rise by a factor of ten to one.

Together with sea water inundation and flood damage, this can have disastrous consequences for the built environment – and property and business interruption insurers. The surge that overwhelmed New Orleans following Hurricane Katrina, and the subsequent cascading collapse of critical infrastructure, offered a glimpse of the sort of scenario underwriters fear. “We’re going down and the sea is coming up,” confirms Gilles Erkens, of the Deltares Research Institute in Utrecht. “Potential losses could run into hundreds of millions of dollars every year.”

The causes are varied. Foremost is large-scale groundwater extraction for drinking water and industrial processes – although elsewhere, like Los Angeles, it is oil and gas extraction that is to blame. Some urban areas are also constructed on multiple layers of soft soil, which compacts when built on – one of the problems facing New Orleans, for instance, and a feature of megacities that spring up on river deltas, such as Guangzhou in south west China.

One of the most severely affected cities was Tokyo, which grew rapidly in the middle of the last century and sunk over four metres as a result – until drastic remedial measures were put in place in the 1970s to restrict the extraction of groundwater. Since then the subsidence has stabilised. But from Jakarta and Dhaka to Venice, the risks are still all too real…

Jakarta is subsiding faster than any other megacity. The northern part has sunk by nearly four metres in the last 35 years, mainly due to groundwater extraction as the population has mushroomed and former agricultural land has been taken over by massive residential and industrial developments.

...Venice sunk about 120mm in the 20th century due to natural and human causes. In addition, the sea level rose about 110mm. A range of measures – such as restrictions on groundwater extraction – were introduced to stabilise the problem. But recent satellite mapping suggests these may not be enough, as the city is still subsiding by one to two millimetres a year. The causes are two-fold....

A waterside shanty in Jakarta, shot by Thehero, Wikimedia Commons, under the Creative Commons 2.0 license

Lacking statewide strategy, New Jersey shore towns prepare for climate change

Carolyn Beeler at Newsworks.org: Hurricane Sandy was a harsh wake-up call for Jersey shore communities, a reminder of their vulnerability in the face of predicted sea-level rise, more intense storms and increasingly frequent coastal flooding.

Now that post-storm cleanup and rebuilding is slowing, New Jersey shore communities, aided by non-profits and academic centers, are developing comprehensive resiliency plans to better prepare for the longer-term challenges of climate change.

...With immediate repairs now over, Tuckerton and many other municipalities are beginning to grapple with planning for a much longer-term challenge: sea-level rise. Rutgers researchers project sea level will rise between 13 to 28 inches by 2050, while New Jersey itself gradually sinks.

...The Borough of Tuckerton joined with surrounding Little Egg Harbor Township for Sandy cleanup and resiliency planning. Still, administrator Jenny Gleghorn said it feels like a tiny town facing a huge challenge. "If the state of New Jersey would just say, 'This is the type of thing that you need to do, and here's some funding to help that out,' I think a lot of towns would benefit from that," Gleghorn said. "We can't be the only towns that are in this situation."

....Still, floodplain manager John Miller and some of the most vocal environmental groups in the state see the rule change as a missed opportunity to incorporate lessons learned from Sandy into coastal land use policy. In the face of rising seas, he argues putting more people in low-lying areas near the coast will make it harder to evacuate them, or reach them with emergency services....

Hurricane Sandy eats a rollercoaster in New Jersey, New Jersey National Guard photo