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E-waste in the environment - an overview of data

Submitted by: Rick Higgins - Published At: 2015-02-23 14:42 - (773 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 - (1924 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 - (820 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.

Sea level change - An EC perspective on the evidence presented in IPCC's 5th Assessment Report

Submitted by: Rick Higgins - Published At: 2014-11-16 10:51 - (518 Reads)
Marine and Oceans
More than seventy percent of the World’s surface is covered by water. Between 1901 and 2010 AR5 states that it is “very likely” the global mean rate of sea level rise was 1.7 (1.5 to 1.9) millimetres per year (mm/yr) for a total sea level rise of 0.19 (0.17 to 0.21) metres (m) or 19 centimetres (cm). In recent decades global mean sea level (GMSL) has continued to rise, and at an increased rate. Between 1993 and 2010, the rate was 3.2 (2.8 to 3.6) mm/yr.

For the first time observations are now available for each of the contributions to the observed GMSL change (from such contributing factors as thermal expansion, melting glaciers and ice sheets), as a result of improved and new observations of the ocean since the introduction of satellite radar altimetry in 1993. Observations indicate that 90% of anthropogenic heat added to the climate system has been in the oceans.

During the last interglacial period (~129,000 to 116,000 years ago) global mean sea level (GMSL) was, for several thousand years, between a minimum of 5m ("very high confidence") and a maximum of 10m ("high confidence") higher than present. AR5 concludes with “high confidence” that sea level data indicate a transition in the late 19th century to the early 20th century from relatively low mean rates of rise over the previous two millennia to higher rates of rise. Over the past 2,000 years there is "medium confidence" that fluctuations in GMSL did not exceed ~ +/- 0.25m (or 25cm). Sea Level Change(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.

High resolution analysis provides important new insights into abrupt climate change

Submitted by: Geoff Zeiss - Published At: 2014-10-20 18:08 - (417 Reads)
Climate
This high-resolution study provides important new insights into both the onset and evolution of abrupt climate change. Using a new analytical technique, temperature and other key variables have been measured in Greenland ice cores at better than yearly resolution for the first time. The study analyzed three abrupt climate events (two warming and one cooling) in the period from 15.5 to 11 thousand years ago. The high-resolution records reveal that the two warming events involved a warming from glacial to warm interglacial of more than 10 °C. The warming transition beginning 14,700 years ago occurred within only three years. The other warming transition 11,700 years ago extended over 60 years. The high-resolution records demonstrate that the two warming events followed the same general pattern involving a sudden shift over one to three years in polar atmospheric circulation. Steffensen et al., Science 2008: Vol. 321 no. 5889 pp. 680-684 DOI: 10.1126/science.1157707 (external link)