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5 trillion pieces of plastic floating on World's oceans

Submitted by: Rick Higgins - Published At: 2015-04-26 00:20 - (154 Reads)
Marine and Oceans
A recent evidence-based study(external link) has been released which estimates the amounts of plastics floating on the oceans. The study is based on extensive surveys from 24 expeditions across the five major rotating ocean current regions (known as ocean gyres) of the sub tropics as well as coastal Australia, the Bay of Bengal and the Mediterranean Sea. The study estimates ("our estimates are highly conservative") there are in the order of 5.25 trillion pieces of plastic weighing around 270,000 tonnes currently floating on the surface of the oceans. As around 8 million tonnes of plastic waste is added to the World's oceans annually the majority of it sinks to the ocean floor. Plastics take in the order of 5 to 40+ years to break up and degrade/decompose in the oceans, depending on their chemical and physical composition. Some are ingested by marine life and some eventually find their way into the food chain for human consumption. Every year around 100,000 marine mammals and turtles are killed by plastic litter. A second recent study(external link) takes available data on plastics entering the oceans from major sources and models the dynamics of how the plastics are flushed from these land sources into the major ocean regions and demonstrates the subsequent transport of plastics by wind and current around the World. Together these 2 studies provide new, more robust estimates of the global situation.


Extent of summer Arctic sea ice may help predict Northern Hemisphere weather patterns

Submitted by: Geoff Zeiss - Published At: 2015-02-26 01:57 - (184 Reads)
Climate
The Arctic Ocean, which is a small body of water compared to the Pacific or the Atlantic oceans, is not considered to be a major determinant of global weather patterns. But in 2009 Jennifer Francis and her colleagues published a paper presenting evidence that the recent faster warming in the Arctic, called Arctic amplification, is changing broader Northern Hemisphere weather patterns. The authors hypothesize possible mechanisms by which the Arctic could influence broader weather patterns. The most controversial of these is the suggestion that decreasing ice extents reduces the temperature gradient between high and mid-latitudes which results in slowing the jet stream which has important implications for Northern Hemisphere weather patterns. A potential application of this research is that summer sea extents could be used to predict Northern Hemisphere weather in the following autumn and winter which would be of value for weather forecasting in the Northern Hemisphere. Francis et al (2009), Geophys. Res. Lett., 36,L07503.(external link)

E-waste in the environment - an overview of data

Submitted by: Rick Higgins - Published At: 2015-02-23 14:42 - (1129 Reads)
Waste
Electronic and electrical waste (e-waste for short) is reported (by the World Bank in 2012) to be growing faster than any other waste stream. Approximately 49 million tonnes of e-waste was generated globally in 2012. Of this the EU generated approximately 20% or 9.9 million tonnes, the USA 19% or 9.4 million tonnes and China 15% or 7.3 million tonnes. Three categories account for almost 90% of the generation of e-waste: large household appliances 42%, information and communication technology equipment 34% and consumer electronics 14%. E-waste comprises more than 5 per cent of all municipal waste - around the same amount as all plastic packaging. Rapid increase in the generation of e-waste is driven by the continually growing global electronics market and a concurrent rise in obsolescence rates of electronic and electrical equipment. E-waste can contain toxic materials which present significant environmental issues. It can also contain components and materials which have potential value when recycled. Reliable comparative e-waste data is not yet available at the global level; see Editor's comments below regarding data coverage, definitions and reliability.


The cryosphere and climate change - An EC perspective on the evidence presented in IPCC's 5th Assessment Report

Submitted by: Rick Higgins - Published At: 2014-11-16 11:08 - (2871 Reads)
Climate
The term cryosphere refers to those parts of the Earth’s surface where water is in solid form. This includes ice in glaciers, ice sheets and sea ice as well as permafrost (frozen ground) and snow. The cryosphere plays a major role in the global climate system and impacts such critical environmental factors as sea level, the water cycle, surface energy budgets and methane production. The IPCC 5th Assessment Report (AR5) focuses on the cryosphere as one of its main themes. The report (AR5 chapter 4) concludes (with high confidence) that over the last two decades glaciers have continued to shrink almost worldwide, the Greenland and Antarctic ice sheets have been losing mass and Arctic sea ice and Northern Hemisphere spring snow cover have continued to decrease in extent. The report also concludes that multiple lines of evidence support very substantial Arctic warming since the mid-20th century. In addition there is more data every year indicating a continuing increase in permafrost thawing (which leads to the release of methane). IPCC AR5, Chapter 4 - Cryosphere(external link)
This article is one of a series of eight providing an EnvironmentCounts.org (EC) perspective on various aspects of IPCC's AR5. Each article focuses on the primary data and related evidence presented and specifically excludes coverage of projections, as per EC's editorial policy and guidelines.

The oceans and climate change - An EC perspective on the evidence presented in IPCC's 5th Assessment Report

Submitted by: Rick Higgins - Published At: 2014-11-16 11:02 - (1098 Reads)
Marine and Oceans
The Fifth Assessment Report (AR5) of the IPCC states there is strong evidence that four global measures of ocean change have increased since the 1950s: the inventory of anthropogenic carbon dioxide, global mean sea level, upper ocean heat content, and the salinity contrast between regions of high and low sea surface salinity.
About 93% of the excess heat energy stored by the earth over the last 50 years is found in the ocean and changes in ocean heat content dominate changes in the global energy inventory. The report states that global mean sea level (GMSL) rose by 0.19 (0.17 to 0.21) m over the period 1901 to 2010. The rate of sea level rise since the mid-19th century has been larger than the mean rate during the previous two millennia (high confidence). The report concludes with high confidence that the observed patterns of change in the subsurface ocean are consistent with changes in the surface ocean in response to climate change and natural variability and with known physical and biogeochemical processes in the ocean. IPCC AR5 Chapter 3: Observations: Ocean(external link)

This article is one of a series of eight providing an EnvironmentCounts.org (EC) perspective on various aspects of IPCC's AR5. Each article focuses on the primary data and related evidence presented and specifically excludes coverage of projections, as per EC's editorial policy and guidelines.