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Environmental Monitoring


March 2016 Issue

North Atlantic Absorbs
More Carbon Dioxide

A University of Miami (UM) Rosenstiel School of Marine and Atmospheric Science-led study shows the North Atlantic absorbed 50 percent more man-made carbon dioxide over the last decade, compared to the previous decade. The findings show the impact that the burning of fossil fuels have had on the world’s oceans in just 10 years.

The North Atlantic is an area of high carbon dioxide uptake and storage due to large-scale ocean circulations. The uptake of carbon dioxide has many impacts on ocean-dwelling organisms by decreasing ocean pH. The findings have important implications for marine organisms, such as corals and mollusks, which require a certain pH level in the surrounding water to build their calcium carbonate-based shells and exoskeletons.

The researchers hope to return in another 10 years to determine if the increase in carbon uptake continues, or if it will decrease as a result of slowing thermohaline circulation.

New Colombia Survey
Awarded to CGG

CGG was awarded an extension to a major 3D seismic survey it successfully completed on the Caribbean coast offshore Colombia in late 2015. The new survey follows the original 16,000-sq. km survey CGG conducted over portions of the Col-1 and Col-2 blocks, which was the largest survey ever recorded offshore Colombia.

This major extension was expected to start in February 2016. The additional data will be processed in CGG’s Houston subsurface imaging center.

EM 2040C to Survey
Dutch Waters

The Dutch Ministry of Infrastructure and Environment has selected the Kongsberg Maritime EM 2040C very high-resolution, shallow-water multibeam system to spearhead its inland waterway survey operations. The Ministry ordered five EM 2040C dual-head and dual-swath systems, and the contract provides the option for additional systems, up to a maximum of 11 within the next 10 years. Kongsberg Maritime was also awarded a maintenance and management contract to be serviced and coordinated from the Kongsberg Maritime Holland office.

The Dutch Ministry of Infrastructure and Environment is responsible for 2,137 km of canals and rivers and 5,472 km of waterways throughout the Netherlands, which must be surveyed on a regular basis to ensure safety of navigation. The EM 2040C systems will be the primary tool to survey these waters on an ongoing basis. The first five systems were delivered at the end of 2015, with remaining units ordered to be delivered on demand when the vessels are available.

Earth Enters
Age of Plastic

Planet Earth’s oceans and lands will be buried by increasing layers of plastic waste by midcentury due to human activity, according to research led by the University of Leicester.

A new study examines the evidence that we now live in the Anthropocene, an epoch where humans dominate the Earth’s surface geology, and suggests that the surface of the planet is being noticeably altered by the production of long-lasting man-made materials, resulting in the “Age of Plastic”.

The study suggests that plastics have such a long-lasting impact on the planet’s geology because they are inert and hard to degrade. When plastics litter the landscape they become part of the soil, often ending up in the sea and being consumed by and killing plankton, fish and seabirds.

Plastics can travel thousands of miles, caught up in the great oceanic garbage patches or eventually washed up on distant beaches. Plastics can eventually sink to the seafloor. Once buried, plastics have a good chance to be fossilized, thus becoming archaeological and geological materials. They are increasingly found as inclusions in recent strata and make excellent stratigraphic markers.

In 2016, the Anthropocene Working Group will gather more evidence on the Anthropocene, which will help inform recommendations on whether this new time unit should be formalized and, if so, how it might be defined and characterized.

Permafrost Thawing
Affects Community Life

Alaska’s thawing permafrost soils cost the U.S. several 100 million dollars every decade, primarily because airports, roads, pipelines and settlements require relocation as a result of sinking ground and eroding river banks. An international team of researchers has now measured riverbank erosion rates that exceed all previous records along the Itkillik River in north Alaska. In a stretch of land where the ground contains a particularly large quantity of ice, the Itkillik River eats into the river bank at 19 m per year, researchers report.

These results demonstrate that permafrost thawing is not exclusively a slow process, but that its consequences can be felt immediately.

Researchers investigated the Itkillik River at a location where the river cuts through a plateau and the subsurface comprises 80 percent pure ice and 20 percent frozen sediment. This ground ice is between 13,000 and 50,000 years old, extends column-like to depths of more than 40 m and, in the past, stabilized the riverbank zone.

These stabilization mechanisms fail if two factors coincide: the river carries flowing water over an extended period and the riverbank consists of a steep cliff, the front of which faces south and therefore is exposed to a lot of direct sunlight.

From 2007 to 2011, the approximately 700-m-long, 35-m-high cliff retreated up to 100 m. A land area of approximately 31,000 sq. m was lost in this time.

The rate at which a riverbank retreats in permafrost regions depends on the ice content of the soil and other geographical factors. With the increasing mean temperatures in the Arctic, the Itkillik River demonstrates the speed at which erosion can take place.

The objective is to apply this research to planning new settlements, power routes and transport links.


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