Melting of Himalayan glaciers has doubled in recent years

By: Thomas Schmitt Attorney on June 19, 2019 / comment : 0 Asia, Bhutan, China, Climate Change, Earth Science, Environment, Natural Heritage, Nepal

A newly comprehensive study shows that melting of Himalayan glaciers caused by rising temperatures has accelerated dramatically since the start of the 21st century. The analysis, spanning 40 years of satellite observations across India, China, Nepal and Bhutan, indicates that glaciers have been losing the equivalent of more than a vertical foot and half of ice each year since 2000—double the amount of melting that took place from 1975 to 2000. The study is the latest and perhaps most convincing indication that climate change is eating the Himalayas' glaciers, potentially threatening water supplies for hundreds of millions of people downstream across much of Asia.

Changri Nup Glacier, one of the hundreds studied by the researchers. Much of it is covered by rocky debris. The peak of Mt. Everest is in the background at left [Credit: Joshua Maurer]

"This is the clearest picture yet of how fast Himalayan glaciers are melting over this time interval, and why," said lead author Joshua Maurer, a Ph.D. candidate at Columbia University's Lamont-Doherty Earth Observatory. While not specifically calculated in the study, the glaciers may have lost as much as a quarter of their enormous mass over the last four decades, said Maurer. The study appears this week in the journal Science Advances.

Currently harboring some 600 billion tons of ice, the Himalayas are sometimes called the earth's "Third Pole." Many other recent studies have suggested that the glaciers are wasting, including one this year projecting that up to two-thirds of the current ice cover could be gone by 2100. But up to now, observations have been somewhat fragmented, zeroing in on shorter time periods, or only individual glaciers or certain regions. These studies have produced sometimes contradictory results, both regarding the degree of ice loss and the causes.

The new study synthesizes data from across the region, stretching from early satellite observations to the present. The synthesis indicates that the melting is consistent in time and space, and that rising temperatures are to blame. Temperatures vary from place to place, but from 2000 to 2016 they have averaged 1 degree Centigrade (1.8 degrees Fahrenheit) higher than those from 1975 to 2000.

Maurer and his colleagues analyzed repeat satellite images of some 650 glaciers spanning 2,000 kilometers from west to east. Many of the 20th-century observations came from recently declassified photographic images taken by U.S. spy satellites. The researchers created an automated system to turn these into 3-D models that could show the changing elevations of glaciers over time. They then compared these images with post-2000 optical data from more sophisticated satellites, which more directly convey elevation changes.

Artist conception of the KH-9 HEXAGON satellite [Credit: National Reconnaissance Office]

They found that from 1975 to 2000, glaciers across the region lost an average of about 0.25 meters (10 inches) of ice each year in the face of slight warming. Following a more pronounced warming trend starting in the 1990s, starting in 2000 the loss accelerated to about half a meter (20 inches) annually. Recent yearly losses have averaged about 8 billion tons of water, or the equivalent 3.2 million Olympic-size swimming pools, says Maurer. Most individual glaciers are not wasting uniformly over their entire surfaces, he noted; melting has been concentrated mainly at lower elevations, where some ice surfaces are losing as much as 5 meters (16 feet) a year.

Some researchers have argued that factors other than temperature are affecting the glaciers. These include changes in precipitation, which seems to be declining in some areas (which would tend to reduce the ice), but increasing in others (which would tend to build it). Another factor: Asian nations are burning ever-greater loads of fossil fuels and biomass, sending soot into the sky. Much of it eventually lands on snowy glacier surfaces, where it absorbs solar energy and hastens melting.

Maurer agrees that both soot and precipitation are factors, but due to the region's huge size and extreme topography, the effects are highly variable from place to place. Overall, he says, temperature is the overarching force. To confirm this, he and his colleagues compiled temperature data during the study period from ground stations and then calculated the amount of melting that observed temperature increases would be expected to produce. They then compared those figures with what actually happened. They matched. "It looks just like what we would expect if warming were the dominant driver of ice loss," he said.

Ice loss in the Himalayas resembles the far more closely studied European Alps, where temperatures started going up somewhat earlier, in the 1980s. Glaciers there started wasting shortly after that increase, and rapid loss of ice has continued since then. The Himalayas are generally not melting as fast as the Alps, but the general progression is similar, say the researchers. The study does not include the huge adjoining ranges of high-mountain Asia such as the Pamir, Hindu Kush or Tian Shan, but other studies suggest similar melting is underway there as well.

Oblique view of the Himalayas on the border of Sikkim, India and eastern Nepal, captured Dec. 20, 1975 by a KH-9 HEXAGON spy satellite. Such declassified images were used by researchers in a new study of Himalayan glaciers [Credit: Joshua Maurer]

Some 800 million people depend in part on seasonal runoff from Himalayan glaciers for irrigation, hydropower and drinking water. The accelerated melting appears so far to be swelling runoff during warm seasons, but scientists project that this will taper off within decades as the glaciers lose mass. This, they say, will eventually lead to water shortages.

A separate study published this May estimates that yearly runoff is now about 1.6 times greater than if the glaciers were replenished at the same rate they were melting. As a result, in many high-mountain drainages, meltwater lakes are building rapidly behind natural dams of rocky debris; these are threatening downstream communities with potentially destructive and deadly outburst floods. Even on Mount Everest, long-lost corpses of climbers who failed to return are emerging from melting ice and snow along trails.

The study shows that "even glaciers in the highest mountains of the world are responding to global air temperature increases driven by the combustion of fossil fuels," said Joseph Shea, a glacial geographer at the University of Northern British Columbia who was not involved in the study. "In the long term, this will lead to changes in the timing and magnitude of streamflow in a heavily populated region."

"It shows how endangered [the Himalayas] are if climate change continues at the same pace in the coming decades," said Etienne Berthier, a glaciologist at France's Laboratory for Studies in Geophysics and Spatial Oceanography, who also was not involved in the study.

Source: Columbia University [June 19, 2019]

Asian elephants may lose up to 42 percent of suitable habitats in India and Nepal

By: Thomas Schmitt Attorney on February 28, 2019 / comment : 0 Climate Change, Ecosystems, India, Natural Heritage, Nepal, Wildlife

Protecting and expanding suitable habitats for wildlife is key to the conservation of endangered species, but owing to climate and land use change the ideal habitats of today may not be fitting in 30 or 50 years. An international team of scientists therefore predicted range shifts of Asian elephants in India and Nepal using species distribution models based on distribution data for the elephants and climate projections. While a few regions in the north and northeast of the subcontinent may provide more suitable habitats in the future, overall a heavy loss is probable in all scenarios. The complex effects of environmental change on the distribution of the elephants is elucidated in a paper published in the journal Diversity and Distributions.

Asian elephant [Credit: Priya Davidar & Jean-Philippe Puyravaud]

It is well known that climate change, land use change, changes in water cycles, and other influencing factors will cause redistribution of species – directly or indirectly. The details of these processes are very complex, however, as effects of global change is manifested very differently on a local scale. In a massive effort, scientists from Spain, India, Nepal, Myanmar, Italy, and Germany worked together in order to assess the combined effects of human pressures and climate change on Asian elephants' distribution, embedded in the human-dominated landscapes in India and Nepal. "We compiled a large database of more than four thousand elephant occurrences and a large geodatabase of environmental predictor variables covering India and Nepal for this study," explains Surendra P. Goyal (Wildlife Institute of India). In a first step, this allowed the scientists to predict the current spatial distribution of Asian elephants as a function of environmental variables.

"In addition to ongoing human-induced disturbance, especially in the form of land-use change, elephant distribution is influenced by complex local scale interactions among precipitation and temperature, complicated by seasonal monsoon in this region," explains lead author Rajapandian Kanagaraj from the National Museum of Natural Sciences (MNCN) in Madrid (Spain). The scientists estimated that around 256 thousand square kilometres of habitat are suitable for elephants in India and Nepal.

In a second step the effects of climate changes were included into the distribution model to predict future elephant distributions and possible range shifts. Relying on climate and land use data projections for 2050 and 2070, different scenarios were calculated. All scenarios strongly indicate that the interaction between climate change and land use will compound existing threats to the elephant.

"We anticipate that elephant range would likely shift towards higher elevations in the Himalayas, and along a gradient of water availability, instead of a simple unidirectional range shift towards higher elevations and latitudes typically expected when temperature is the principal factor," explains Miguel B. Araújo, expert on climate change and biodiversity at MNCN, Madrid, in whose lab this collaborative study was undertaken.

In a scenario where only climate change is included, the loss of potential habitat is more moderate, but still substantial with a 17.1 percent loss in one scenario in 2070. "The negative effect is especially severe in the human-dominated landscapes in eastern and southern India," say Priya Davidar and Jean-Philippe Puyravaud (Sigur Nature Trust, India). Gain in potential habitat is indicated in northern and northeastern habitats particularly along the valleys in the Himalayan foothills. "Our model projections suggest that the projected future changes in the distribution of elephants in India and Nepal would be driven mainly by changes in the climatic water balance, followed by changes in temperature and other ongoing human-induced disturbance," Kanagaraj and Araújo conclude.

For that reason, building comprehensive and robust spatial models is crucial to assess the impact of environmental changes in wildlife populations. "The database consisted of 115 environmental variables: 60 climatic, 16 human disturbance, 29 forest and vegetation and 10 topographic variables, all at a grid resolution of 1 kilometre," says Thorsten Wiegand, modelling expert from the Environmental Research Centre (UFZ), Leipzig. Occurrence data relied on 4,626 elephant sightings between 1990 and 2017, with the vast majority of sightings after 2002.

"The art of modelling here was distilling the most biologically plausible environmental predictors and eliminating redundant correlations," Stephanie Kramer-Schadt, head of the department of Ecological Dynamics at the Leibniz Institute for Zoo and Wildlife Research (Leibniz-IZW), explains the methods. The team calculated and tested several models which can forecast the distribution only from the remaining nine environmental variables.

"In the end we have to acknowledge that are dealing with models of distribution and environmental change," Kramer-Schadt adds. This approach enabled the team to develop highly probable scenarios for range shifts of the elephants under global change, but the predictions are always connected with a level of uncertainty.

The results of this comprehensive study nevertheless have important implications concerning conservation efforts as the suitability maps and future projections can be effectively used to identify critical habitat areas that require immediate conservation attempts. Furthermore the projections can inspire adjustments to current habitat protection strategies.

A supplementary analysis highlighted the importance of connected habitats: "The model only predicts the suitability of a 1 km2 grid cell without accounting for the movement capacity of elephants and their home range sizes, so we added the core range analysis to identify high suitability areas larger than the size of two average home ranges and an analysis of the connectivity of core areas that considers the maximal displacement capacity of elephants," says Kanagaraj.

"The results underline the pressure that is expected on the habitats on southern and eastern India as it is where large core areas can be found," says Surendra P. Goyal. Further, the analysis suggests that the fragmented core areas that are located along the foothills forests and floodplains of the Himalaya could be connected by a mixture of poor‐ and high‐quality habitat that should form specific targets for management. These results provide a first assessment of areas that could provide connectivity among core areas.

"We are certain that conservation of remaining habitat will always remain the centrepiece of biodiversity conservation," the team states. "Our study provides a first assessment on the effect of climate change on the distribution of the Asian elephant in its major habitats in India and Nepal, which could help other assessments over its entire range across South and South‐East Asia, and be useful for developing management plans for wildlife conservation under the aegis of climate change."

Source: Forschungsverbund Berlin [February 28, 2019]

Climate change leading to water shortage in Andes, Himalayas

By: Thomas Schmitt Attorney on December 14, 2018 / comment : 0 China, Climate Change, Earth Science, Ecosystems, Environment, India, Natural Heritage, Nepal, Pakistan, Peru, Tibet

Climate change could have devastating effects on vulnerable residents in the Andes mountains and the Tibetan plateau, according to researchers at The Ohio State University who have been studying glaciers in those areas for decades.

Quelccaya glacier [Credit: Ohio State University]

Their findings--that glaciers in both parts of the world are melting more rapidly than at any point in the last 10,000 years--mean the water supply in parts of Peru, Pakistan, China, India and Nepal will decline, soon.

"Supply is down. But demand is up because of growing populations," said Lonnie Thompson, a climate scientist at Ohio State's Byrd Polar and Climate Research Center. "By 2100, the best case scenario is that half of the ice will disappear. Worst-case scenario: two-thirds of it will. And you've got all those people depending on the glacier for water."

Thompson, a distinguished university professor of earth sciences at Ohio State, presented the team's findings on Dec. 14 at the annual meeting of the American Geophysical Union in Washington, D.C.

Thompson has been studying and documenting the effects of climate change on glaciers in Peru for more than 40 years. The glaciers there supply critically needed water for people, crops and livestock. In 2016, Thompson and researchers in China and India launched a research initiative to conduct similar research on the Tibetan plateau, which holds thousands of glaciers that supply water to people in parts of Afghanistan, Bhutan, China, India, Nepal, Pakistan and Tajikistan. The international research team dubbed the plateau the "Third Pole" because it contains the largest stores of freshwater in the world outside of the North and South poles.

Since then, they have drilled ice core samples from across the Tibetan plateau and the Andes mountains, examining the ice for clues about temperature, air quality and other large-scale events in history.

"The last 200 years or so, we really understand," Thompson said. "Now we are looking at the last 10,000 years."

What they are finding is causing him some alarm.

There have been times throughout history when the glacial ice cores showed temperatures increased--during an El Nino, for example. But within the last century, the cores from both the Andes and the Himalayas show widespread and consistent warming.

"This current warming is not typical," Thompson said. "It is happening faster, it is more persistent and it is affecting glaciers in both Peru and India. And that is a problem, because a lot of people rely on those glaciers for their water."

Melting glaciers can trigger such hazards as avalanches and floods. And they also can have long-lasting effects on a region's water supply.

As the glaciers melt, initially those regions will have more water. But over time, as the glaciers shrink, the water those glaciers typically supply will dwindle, Thompson said.

"Precipitation is down and temperatures are up and that leads to retreating glaciers," he said. "There are 202 million people in Pakistan who rely on water from the Indus River--and that river is fed by the glacier.

The effects in Peru, too, could be far-reaching, particularly on Peruvian agriculture and on the water supply in Lima, the Peruvian capital.

Thompson and his team are hoping that by studying the glaciers in both areas, they will find answers to slow glacial retreat--or to provide new water sources to at-risk areas.

"The problems are similar in both the Andes and the Tibetan plateau," he said. "The hope is that by finding solutions, we can help both places."

Source: Ohio State University [December 14, 2018]

Tiger population nearly doubles in Nepal

By: Thomas Schmitt Attorney on September 24, 2018 / comment : 0 Endangered Species, Natural Heritage, Nepal, Wildlife

Nepal's wild tiger population has nearly doubled over the last nine years, officials said Monday, in a victory for the impoverished country's drive to save the endangered big cats.

The wild tiger population in Nepal was counted as 235 in a survey carried out this year, double that in 2009 [Credit: AFP]

Wildlife groups have welcomed the news as a sign that political involvement and innovative conservation strategies can reverse the decline of the majestic Royal Bengal tiger.

A survey carried out earlier this year counted 235 tigers in Nepal, up from around 121 tigers in 2009.

Conservationists and wildlife experts used more than 4,000 cameras and around 600 elephants, trawling a 2,700-kilometre (1,700-mile) route across Nepal's southern planes where the big cats roam.

"This is a result of concentrated unified efforts by the government along with the local community and other stakeholders to protect the tiger's habitat and fight against poaching," Man Bahadur Khadka, director general of Nepal's Department of National Parks and Wildlife Conservation, told AFP.

Deforestation, encroachment of habitat and poaching have devastated big cat numbers across Asia, but in 2010 Nepal and 13 other countries signed a pledge to double their tiger numbers by 2022.

The 2010 Tiger Conservation Plan—which is backed by high profile figures including actor Leonardo DiCaprio—quickly began bearing fruit, and in 2016 the World Wildlife Fund and the Global Tiger Forum announced that the wild tiger population had increased for the first time in more than a century.

In 1900, more than 100,000 tigers roamed the world but that fell to an all-time low of 3,200 in 2010.

DiCaprio tweeted his support for Nepal's success: "I am proud of @dicapriofdn's partnership with @World_Wildlife to support Nepal and local communities in doubling the population of wild tigers."

Ghana Gurung, country representative of WWF in Nepal, said that the country's progress was an example for tiger conservation globally.

"The challenge now is to continue these efforts to protect their habitats and numbers for the long-term survival of the tigers," he said.

Source: AFP [September 24, 2018]

Learning about the Himalayas using Mars technology

By: Thomas Schmitt Attorney on June 20, 2018 / comment : 0 Earth Science, Geology, India, Nepal, Palaeontology

The Himalayan Range includes some of the youngest and most spectacular mountains on Earth, but the rugged landscape that lends it the striking beauty for which it is known can also keep scientists from fully understanding how these mountains formed. "We know more about the rocks on parts of Mars than we do about some of the areas in the Himalaya," said Dr. Alka Tripathy-Lang.

Temple in the Nubra Valley of Ladakh, India, which is in the study area. The picture illustrates the enormous size and scale of the mountains in this part of the Himalayas [Credit: Wendy Bohon]

"Many researchers have done extraordinary geologic mapping in this rugged region, but the fact is that some places are just completely inaccessible because of topography, elevation, or geopolitical issues. The rocks in those areas are an important piece of the tectonic puzzle and are important for understanding the way the region evolved," said Dr. Wendy Bohon. "The tools we used, originally developed for mapping rocks on Mars, were a way to safely access information about the rocks in the Himalayas."

Bohon and colleagues worked with researchers at the Mars Space Flight Facility at Arizona State University to use data from the Earth orbiting satellite Terra in the same way planetary geologists have been using data from the Mars orbiting satellite Odyssey.

Top: Map made using ASTER satellite data imagery. Bottom: one "stretch" - or one color combination - of the ASTER data that was used to make the map [Credit: Geological Society of America]

The researchers relied on the fact that every mineral has a unique spectral "signature," where some parts of the thermal infrared spectrum are absorbed and some parts are reflected. Rocks are made of different combinations of minerals, so when all of these mineral signatures are combined, they reveal the rock type. To easily distinguish between different kinds of rocks the researchers translated these signals into red/green/blue imagery, which results in a distinguishable color for each rock type that can be used to map the distribution of rocks throughout the region.

To double-check that the colors they're mapping are truly the rock type predicted by the imagery, the researchers took hand samples from accessible locations in the study area to the laboratory and measured the spectral signatures of each rock using a thermal emission spectrometer. Then they compared these laboratory signatures to those collected from the ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) instrument on the Terra satellite. They matched. "There is some variation between the lab and ASTER spectral signatures due to different factors like weathering and the averaging area, but overall the match between them was surprisingly consistent," said Tripathy-Lang.

This chart shows the laboratory-collected spectral signature of two different types of rocks from the field area  (shown by black lines) compared with the ASTER spectral signature of areas that displayed the color associated with that rock type in the ASTER imagery (shown with colored lines). The close match of the lines shows that  the rock that was measured and identified in the laboratory is the same type of rock identified by the remote sensing data [Credit: Geological Society of America]

The map they created revealed some interesting geology. They were able to clearly see "suture zones" -- ancient seafloor pushed up and exposed during the collision between India and Eurasia -- as well as subtle differences in the granitic mountains that indicates different phases of formation. They were also able the see the intersection of two massive fault systems, the Karakoram and Longmu Co Faults. "These fault systems are hugely important to the story of the Himalayan-Tibetan collision, and determining the way that these systems have evolved and how they interact is critical for understanding this part of the Himalayan Mountains," said Bohon.

The study is published in Geosphere.

Source: Geological Society of America [June 20, 2018]

New York Met returns stolen idols to Nepal

By: Thomas Schmitt Attorney on April 05, 2018 / comment : 0 Archaeology, Asia, Heritage, Nepal, South Asia, USA

A pair of rare idols stolen from Nepal three decades ago were returned to the country on Wednesday by New York’s Metropolitan Museum of Art.

The 700-year-old standing statue of the Buddha [Credit: AFP]

The two statues — one of Buddha and the other of the Hindu god Shiva and his wife Parvati — were stolen in the 1980s when rampant looting saw many important artefacts whisked out of Nepal and into the hands of private collectors.

“The government was unaware of the whereabouts of the statues until historian Lain Singh Bangdel mentioned (in a book) that the statues were on display at the Metropolitan Museum of Art in New York,” Shyam Sundar Rajbanshi of Nepal’s Department of Archaeology said.

The 11th-century Shiva statue, known as the Uma Maheshwor idol, was given to the Met in 1983 while the Buddha — estimated to be around 700 years old — was donated by a private collector in 2015.

The 11th-century Uma Maheshwor stele [Credit: AFP]

The two statues were removed from display after the Met learned they were stolen, local media reported.

The statues will now be showcased at the National Museum of Nepal in the capital Kathmandu, Mr. Rajbanshi confirmed.

Nepal’s rich cultural heritage was ravaged by decades of theft from the 1960s to 1980s. Natural disasters and unchecked development also encroached on ancient sites.

A devastating earthquake in April 2015 caused extensive damage in the Kathmandu Valley, home to hundreds of sacred Buddhist and Hindu sites.

The UN’s cultural agency UNESCO warned if not properly conserved those sites could lose their coveted world heritage status.

Source: AFP [April 05, 2018]