Category Archives: Sea Level Rise

Kiribati Conference: Voices From the South Pacific

kiribati
Old pier, Kanton island. Kanton is the largest, northernmost island of the Phoenix Islands, in the Republic of Kiribati. Photo source: ©© Naomi

Excerpts;

Located and spread across the central Pacific, Kiribati, a low-lying chain of islands, is one of the most vulnerable countries to climate change, and it is already feeling some of the impacts.

About 40 officials from around the world have flown to the tiny atoll nation of Kiribati to take a look at the immediate impact climate change is having on the Pacific nation…

Read Full Article, The Sydney Morning Herald

The Guardian, UK

Bangladesh: Finding Sustainable Ways to Cope with Sea Level Rise

floating-gardens
Floating gardens in the Wetland Research and Training Centre (WRTC) run by the Bangladesh Center for Advanced Studies. Captions and Photo source: ©© Aarjan Dixit, World Resources Institute

By IRIN, Human News and Analysis

As swollen monsoon rivers and rising sea levels threaten to engulf more land across Bangladesh, NGOs are training thousands of farmers in traditional soil-less farming on water.

Agriculture accounts for almost a quarter of Bangladesh’s gross domestic product and provides work for 62 percent of the labour force.

Yet in a country frequently flooded and recognized as one of the most vulnerable to climate change, floating vegetable beds have become a fruitful farming alternative. The process is similar to hydroponics, which uses a non-biological growing material like gravel, whereas floating farms use beds made of water hyacinth, bamboo and other aquatic plants.

“The productivity of this farming system is 10 times higher than traditional land-based agricultural production in the southeast of Bangladesh,” said Papon Deb, project manager for the Wetland Resource Development Society (WRDS).

WRDS is one of several NGOs, along with CARE, the International Union for the Conservation of Nature (IUCN), and Practical Action, working around the country to train thousands of farmers.

Bangladesh has had floating farms for hundreds of years, primarily in low-lying areas in the south where land is submerged most of the year.

“Soil-less agriculture evolved through people’s initiative for adaptation to an adverse environment,” said A.H.M. Rezaul Haq, a WRDS researcher. “It has been a part of the indigenous form of cultivation since our forefathers.”

The plant bed, built using several layers of water hyacinth and bamboo, is typically 15-50m in length, 1.5-2m wide and 0.6-0.9m thick. Semi-decomposed aquatic plants are then added to the mix and left to sit for several days before it is ready to be seeded. The beds can be prepared in any depth of water. Farmers can stand on some of them or manoeuvre around them in boats.

The floating beds are anchored to prevent them from drifting out into larger bodies of water, and covered in netting to keep out ducks and other fowl that might eat the crops, said Faruk Ul Islam, head of organizational development for Practical Action, which is training farmers in 600 villages in the north on this practice. Some farmers have to swim out to retrieve beds that have strayed into open water.

Many villagers use the previous year’s decomposed bed as organic fertilizer. These new beds are kept intact thanks to bamboo poles on the sides.

Floating Farms
Floating farms are 10 times more productive than land-based farms, experts say.Wetland Resource Development Society. Photo Source: IRIN

Islam says the floating garden set-up is virtually free, with water and water hyacinth widely available in the waters of Bangladesh. The cost of setting up the floating bed for the growing season might be as little as US$3 for seeds and labour, or as much as $9 if a farmer has to also buy bamboo and netting.

Haq’s team said villagers in Chandra have grown 23 different types of vegetable and five types of spices on floating beds, including okra, cucumbers, bitter gourds, eggplants, beans, tomatoes, cauliflowers, turnips, radishes, carrots, ginger and garlic.

Several research and development organizations are now working with thousands of farmers across the country to implement floating garden projects. While the practice is common in the south, where huge floating farms look like land masses from the air, development workers are now teaching people in northern areas more recently prone to flooding.

The southwestern village of Chandra long ago famed for its mango, jackfruit and dates, is one area where water levels rise more than two metres during the monsoon rains and remain high for 2-3 months.

Now, with this project, there are over 1,000 villagers involved and fewer people are migrating to the city.

Original Article: Spreading the floating farms tradition, Bangladesh, IRIN

Archaeological Sites and Rising Seas: The Channel Islands’ Region

channel-islands
The Channel Islands Region, California.
Photo Source: NASA

Excerpt from the Smithsonian Institution

Should global warming cause sea levels to rise as predicted in coming decades, thousands of archaeological sites in coastal areas around the world will be lost to erosion. With no hope of saving all of these sites, archaeologists Torben Rick from the Smithsonian Institution, Leslie Reeder of Southern Methodist University, and Jon Erlandson of the University of Oregon have issued a call to action for scientists to assess the sites most at risk.

Writing in the Journal of Coastal Conservation and using California’s Santa Barbara Channel as a case study, the researchers illustrate how quantifiable factors such as historical rates of shoreline change, wave action, coastal slope and shoreline geomorphology can be used to develop a scientifically sound way of measuring the vulnerability of individual archaeological sites. They then propose developing an index of the sites most at risk so informed decisions can be made about how to preserve or salvage them.

Urban development, the researchers point out, also is a significant threat to the loss of archaeological data. Coastlines have long been magnets of human settlement and contain a rich array of ancient archaeological sites, many of which have never been excavated. Urban development is projected to remain high in coastal areas, representing a significant danger to undisturbed sites.

Thousands of archaeological sites, from large villages and workshops to fragmented shell middens and lithic scatters, are perched on the shorelines and sea cliffs of the Santa Barbara Channel, the researchers point out.

Santa Rosa, Channel Islands
Santa Barbara Channel Islands, Santa Rosa and Santa Cruz.
Photo Source: NASA

The archaeological record is never static, and the materials left behind by one generation are altered by the people and environment of the next. However, increasing threats from modern urban development, sea level rise and global warming are poised to increase this steady pattern of alteration and destruction.

The vulnerability of sites in the Santa Barbara Channel is generally lower than sites located along more open, more gently sloped or unstable coastlines, such as the Atlantic and Gulf coasts of North America.

Original Article

Our disappearing past: a GIS analysis of the vulnerability of coastal archaeological resources in California’s Santa Barbara Channel region. Journal of Coastal Conservation


Native artifacts being washed away by rising surf: The Channel Islands, California; AP /NBC

Channel Islands Artifacts
Chumash Indians of the Channel Islands’ artifacts. To the left are bone tools and dagger. The black and white piece is a bone piece laden with asphaltum and shell beads, which may create a better grip. Along the top are different kinds of shell beads. Photo Source: Travis S, Santa Barbara Museum of Natural History

Excerpts;

Perched on the edge of this wind-swept Southern California island, archaeologist Jon Erlandson watches helplessly as 6,600 years of human culture, and a good chunk of his career, is swallowed by the Pacific surf.

It was not long ago that this tip of land on the northwest coast cradling an ancient Chumash Indian village stretched out to sea. But years of storm surge and roiling waves have taken a toll. The tipping point came last year when a huge piece broke off, drowning remnants of discarded abalone, mussel and other shellfish that held clues to an ancient human diet.

“There’s an enormous amount of history that’s washing into the sea every year,” Erlandson said matter-of-factly during a recent hike. “We literally can’t keep up.”

The sea has long lashed at the Channel Islands, also known as the North American Galapagos, stripping away beaches, slicing off cliff faces and nibbling at hundreds, perhaps thousands, of cultural relics.

Past coastal erosion for the most part was a natural phenomenon, but the problem is feared to grow worse with human-caused global warming and higher sea levels.

In 2005, the U.S. Geological Survey found that half of the 250 miles of shoreline studied on the Channel Islands were vulnerable to sea level rise. The most at-risk were the San Miguel and Santa Rosa coasts, home to thousands of archaeological relics from house pits to trash heaps to random scatters of stone anvils and burned rocks…

Troubled Islands: Hurricanes, Oil Spill and Sea Level Rise

chandeleur-islands
Oil on the Chandeleur islands from a plane. Captions and Photo source: ©© Jeff Warren

Excerpts;

On one side of the Mississippi River outlet, to the east of the river outlet, is the Chandeleur Islands-Biloxi Marsh system which is on it’s last legs, say researchers studying the recent geological history of the area via peat layers beneath in the marshes. On the other side, to the west, is Grand Isle which is the focus of a study that helps document what conditions BP needs to restore oil-damaged beaches to return to some kind of normal state, at a time when the island itself is undergoing massive and rapid changes due to hurricanes and repeated beach nourishment efforts…

Read Full Article, Science Daily

Arctic Report Card 2010

arctic
Svalbard, Arctic region. Photo source: ©© Bjorn Alfthan / UNEP

Excerpt from NOAA

The Arctic region, also called the “planet’s refrigerator,” continues to heat up, affecting local populations and ecosystems as well as weather patterns in the most populated parts of the Northern Hemisphere, according to a team of 69 international scientists.

The findings were released Oct. 21, 2010 in the Arctic Report Card, a yearly assessment of Arctic conditions…

Read Full Article, Science Daily

NOAA, Report Card

Measuring sea-level rise in the Falklands, 19th-Century Benchmarks Reveal

800px-James_Clark_Ross
Naval officer and polar explorer James Clark Ross (1800–1862). Photo source: ©© Wikimedia

Excerpts;

In 1839, distinguished naval officer and polar explorer James Clark Ross (1800–1862) set off on an expedition to the Southern Ocean with two ships, HMS Erebus and HMS Terror. In April 1842, he stopped at Port Louis, primarily to make magnetic field and other measurements, but also to make repairs to his ships which had been badly damaged in the Drake Passage. Having set up a winter base, he took the opportunity to make careful measurements of sea level relative to two benchmarks cut into the cliffs and marked with brass plaques.

These marks remain in good condition to this day…

Read Full Article, National Oceanography Centre, Southampton, UK

Underwater Robot to Explore Antarctic Ice Shelf

ice-shelf

By University of British Columbia

Scientists predict that the sea ice area around Antarctica will be reduced by more than 33 per cent by 2100, accelerating the collapse of ice shelves. Up to hundreds of metres thick, ice shelves are floating platforms of ice that cover almost half of Antarctica’s coastline.

The mission will study the effect of ice shelves on the mixing of sea water, and will provide critical data for the Antarctica 2010 Glacier Tongues and Ocean Mixing Research Project led by investigator Craig Stevens at the New Zealand National Institute for Water and Atmospheric Research. The field site is located in New Zealand’s Ross Dependency in Antarctica and the team includes scientists from New Zealand, Canada, the United States and France.

Until recently, scientists have had limited ability to access ice-covered waters, but the research team’s use of a high-tech robot aims to change that.

“Few labs in the world are able to investigate the spatial variability of ocean properties under ice,” explains Assoc. Prof. Bernard Laval, head of the UBC Autonomous Underwater Vehicle (AUV) and Fluid Mechanics research group.

“Findings from this study will be unique as there have only been a few under-ice AUV deployments globally, even fewer in the vicinity of ice shelves,” says Laval, who teaches civil engineering in the Faculty of Applied Science.

The AUV, named UBC-Gavia, measures 2.5 metres long by half a metre wide and is equipped with temperature and salinity sensors, current meters, mapping sonar, a digital camera and water quality optical sensors. It will navigate the deep cold waters adjacent to, and possibly under, the floating 100-metre thick Erebus Glacier Tongue in McMurdo Sound, at a latitude of 77° south.

Traveling to Antarctica to operate the AUV are Andrew Hamilton and Alexander Forrest, UBC Civil Engineering PhD candidates in Laval’s lab.

Hamilton and Forrest will pre-plan the AUV missions, setting the flight path and depth for the robot to follow and selecting what sensors to activate. These instructions are uploaded to the AUV, which then dives under the ice collecting data on its own, returning to the ice-hole at the end of the mission.

“The deployments are expected to return important data from a largely uncharted ocean environment,” says Hamilton, who specializes in environmental fluid mechanics.

“Under‐ice datasets will allow us to better understand ice-ocean interactions and provide valuable information for climate modelers.”

Ice Shelf Melting

New Zealand’s Stevens, who worked as a postdoctoral researcher at UBC in the early 1990s, says, “The key is to try and locate the mixing hotspots in time and space. These hotspots appear to be perhaps 1,000 times more energetic than background conditions. The AUV is a key component of our suite of instruments and provides the vital spatial element.”

Original article