Most-recent articles

5 trillion pieces of plastic floating on World's oceans

Submitted by: Rick Higgins - Published At: 2015-04-26 00:20 - (632 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.

Does rapid Arctic warming cause extreme weather in mid- latitudes ?

Submitted by: Geoff Zeiss - Published At: 2015-03-22 15:57 - (516 Reads)
This article investigates the conjecture that the rapidly warming Arctic is more important in determining Northern Hemisphere weather patterns than conventional climate dynamics theory holds. We have discussed a previous 2009 article in which Jennifer Frances and colleagues investigated correlations between summer ice extents in the Arctic and broader Northern Hemisphere weather patterns(see Extent of summer Arctic sea ice may help predict Northern Hemisphere weather patterns(external link)). In this 2012 paper Jennifer Francis and Stephen Vavrus propose a mechanism by which Arctic amplification affects broader Northern Hemisphere weather patterns. They provide evidence that a rapidly warming Arctic weakens the pressure gradient between the Arctic and mid-latitudes which slows the jet stream and increases its waviness. Increased waviness in the jet stream has been statistically linked by recent independent studies to extreme weather in the mid-latitudes. This research is still in its early stages and the detailed mechanism proposed in this paper has not yet been widely accepted.
Jennifer Francis, Stephen Vavrus, Evidence linking Arctic amplification and extreme weather in mid-latitudes 2012(external link)

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

Submitted by: Geoff Zeiss - Published At: 2015-02-26 01:57 - (634 Reads)
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 - (1660 Reads)
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 - (3356 Reads)
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.