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Environmental Monitoring


May 2014 Issue

Accelerated Ice Loss Among West Antarctic Glaciers
Six massive glaciers in West Antarctica are moving faster than they did 40 years ago, causing more ice to discharge into the ocean and global sea level to rise. The amount of ice draining collectively from those glaciers increased by 77 percent from 1973 to 2013, scientists reported in Geophysical Research Letters. Pine Island Glacier, the most active of the studied glaciers, has accelerated by 75 percent in 40 years. Thwaites Glacier, the widest glacier, started to accelerate in 2006, following a decade of stability.

The study is the first to look at the ice coming off the six most active West Antarctic glaciers over such an extended time period. Almost 10 percent of the world’s sea level rise per year comes from these six glaciers. The researchers studied the Pine Island, Thwaites, Haynes, Smith, Pope and Kohler glaciers, all of which discharge ice into the Amundsen Sea Embayment in West Antarctica.

The amount of ice released by these six glaciers each year is comparable to the amount of ice draining from the entire Greenland Ice Sheet annually. If melted completely, the glaciers’ disappearance would raise sea levels another 1.2 meters.

Satellite data was used to look at sequential images of the glaciers from 1973 to 2013. The scientists then calculated how fast the ice was moving by tracking surface features month to month and year to year.

This finding suggests that glacier acceleration models may need to be reevaluated. Most models only take into account isolated speed changes resulting from a local disturbance, rather than representing how these changes affect the glacier as a whole.

Brazil is First Regional Ocean Health Index Site
Brazil was the site of the first Ocean Health Index regional assessment designed to evaluate the economic, social and ecological uses and benefits that people derive from the ocean. Brazil’s overall score was 60 out of 100. The findings, conducted by the University of California, Santa Barbara and Conservation International, appear in PLOS ONE.

The index assesses ocean health with respect to the benefits and services it provides to people now and in the future. Using a scale of 0 to 100, the index scores 10 categories: artisanal fishing opportunities, biodiversity, carbon storage, clean waters, coastal protection, food provision, livelihoods and economies, natural products, sense of place, and tourism and recreation.

Current Climate Change Alters Ocean Environment Faster
The current and projected climate change is altering living conditions in the oceans faster than during comparable events in the past 65 million years, according to Alfred Wegener Institute biologist Dr. Hans-Otto Pörtner.

As a consequence of climate change, three factors are altering marine life living conditions. The most powerful driving force is ocean warming. It is already leading to significant changes. For example, fish species like the Atlantic cod are shifting their habitat poleward. The second factor, ocean acidification, will increase in significance in the coming decades and have substantial impacts globally and in specific ecosystems. The third key development is increasing oxygen deficiency. Its impacts are felt in coastal regions, where the number of oxygen-deficient zones has risen significantly.

Pörtner is participating in the Intergovernmental Panel on Climate Change (IPCC), which has released a report specifying facts and figures for ocean changes, making predictions, and pointing out the risks and costs climate change will generate. The goal is to achieve a consensus between governments and the scientific community.

BMT Creates Metocean Solutions for Tullow’s Offshore Activities
BMT ARGOSS (Marknesse, Netherlands) has been contracted for a number of metocean assessments for Tullow Oil plc (London, England), including comprehensive overviews of meteorological and oceanographic conditions in West Africa and South America, to help support offshore oil and gas exploration and operating activities.

Using numerical modeling techniques and analytical tools, BMT is working closely with Tullow to generate a range of spatial and temporal wind, wave and current data products to interpret the metocean climate in the two target regions.

BMT is also collaborating with Tullow on the development of an online metocean and weather forecasting portal that will provide secure and rapid access to all Tullow’s metocean information via a single gateway.

NOAA Studies Effects of Multiple Stress Factors on Dolphins
Galveston Bay, Texas, recently experienced both an oil spill and harmful algae blooms. Marine sentinels, like bottlenose dolphins in the Gulf of Mexico, share this coastal environment with humans and consume food from many of the same sources. Studying bottlenose dolphins may alert humans to the presence of chemical pollutants, pathogens, and toxins from algae that may be in Gulf waters, according to NOAA. Texas waters have a diverse array of harmful algae. Additional environmental threats include oil spills, stormwater, agricultural runoff and industrial pollution.

A few types of algae produce toxins that can harm fish, mammals, and birds and cause illness in humans. During harmful algal blooms, the high toxin levels often result in illness or death for some marine life, and low-level exposure may compromise their health and increase susceptibility to other stressors.

On March 14, Texas officials closed Galveston Bay to shellfish harvesting after detecting elevated levels of Dinophysis, a harmful algae that can produce toxins resulting in diarrhetic poisoning when people eat contaminated shellfish.

Four days later, Pseudo-nitzschia was detected in Galveston Bay, which is an algae that produces a potent neurotoxin affecting humans, birds and marine mammals. Four days after harmful algae were found in Galveston Bay, it was hit with a 168,000-gallon oil spill.

These events could be a “perfect storm” along the Texas coast, creating an opportunity to study the effects of multiple stressors on these animals.


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