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Climate Change


Climate change has long-since ceased to be a scientific curiosity, and is no longerjust one of many environmental and regulatory concerns. As the United Nations Secretary General has said, it is the major, overriding environmental issue of our time, and the single greatest challenge facing environmental regulators. It is a growing crisis with economic, health and safety, food production, security, and other dimensions.

Shifting weather patterns, for example, threaten food production through increased unpredictability of precipitation, rising sea levels contaminate coastal freshwater reserves and increase the risk of catastrophic flooding, and a warming atmosphere aids the pole-ward spread of pests and diseases once limited to the tropics.

The news to date is bad and getting worse. Ice-loss from glaciers and ice sheets has continued, leading, for example, to the second straight year with an ice-free passage through Canada’s Arctic islands, and accelerating rates of ice-loss from ice sheets in Greenland and Antarctica. Combined with thermal expansion—warm water occupies more volume than cold—the melting of ice sheets and glaciers around the world is contributing to rates and an ultimate extent of sea-level rise that could far outstrip those anticipated in the most recent global scientific assessment.


To strengthen the ability of countries, in particular developing countries, to integrate climate change responses into national development processes.

There is alarming evidence that important tipping points, leading to irreversible changes in major ecosystems and the planetary climate system, may already have been reached or passed. Ecosystems as diverse as the Amazon rainforest and the Arctic tundra, for example, may be approaching thresholds of dramatic change through warming and drying. Mountain glaciers are in alarming retreat and the downstream effects of reduced water supply in the driest months will have repercussions that transcend generations. Climate feedback systems and environmental cumulative effects are building across Earth systems demonstrating behaviours we cannot anticipate.

The potential for runaway greenhouse warming is real and has never been more present. The most dangerous climate changes may still be avoided if we transform our hydrocarbon based energy systems and if we initiate rational and adequately financed adaptation programmes to forestall disasters and migrations at unprecedented scales. The tools are available, but they must be applied immediately and aggressively.

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Mounting scientific evidence suggests that despite global mitigation and adaptation efforts, residual losses and damages from climate change are inevitable. More information is needed on future climate change impacts and on where the limits of adaptation lie.

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The emissions gap and the adaptation gap are increasing. In order to bridge these gaps, it is critical to fill holes in funding, knowledge, technology, capacity and trust.

ThumbnailThe future of the Aral Sea lies in transboundary co-operation

Diversion of water sources has caused the Aral Sea in Central Asia to decline significantly over the past five decades. It has broken into several smaller seas, leaving behind a vast desert and a multitude of environmental, economic and social problems.

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The iconic wildebeest migrations of East Africa are an important ecological phenomenon and massive tourist attraction. However, many wildebeest populations are in drastic decline across the region.

ThumbnailWhere will the water go? Impacts of accelerated glacier melt in the Tropical Andes

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ThumbnailMangrove forest cover fading fast

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ThumbnailFrom Hotspots to Hopespots: Connecting local changes to global audiences

As changes to ecosystems and the environment continue to occur in response to growing population pressure and natural processes, ways to measure and observe these changes on a regular basis will become increasingly important.

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ThumbnailA new eye in the sky: Eco-drones

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Both intensive (industrial) and non-intensive (traditional) forms of meat production result in the release of greenhouse gases (GHGs). As meat supply and consumption increase around the world, more sustainable food systems must be encouraged.

ThumbnailMeasuring Glacier Change in the Himalayas

A serious lack of reliable and consistent data severely hampers scientific knowledge about the state of Himalayan glaciers. As a result, the contribution of glacial melt to the Himalayan river basins remains uncertain.

ThumbnailAfrica without glaciers

Glaciers are one of the planet's important sources of freshwater. Glaciers store and release water seasonally, replenishing the rivers and groundwaters essential for agriculture, domestic supplies, hydroelectricity and industry.

ThumbnailThe Drying of Iran's Lake Urmia and its Environmental Consequences

Lake Urmia, in the northwestern corner of Iran, is one of the largest permanent hypersaline lakes in the world and the largest lake in the Middle East. A combination of drought and increased water diversion for irrigated agriculture within the lake&rspuo;s watershed has decreased the once 100 km² la...

ThumbnailFood Security in the Horn of Africa: The Implications of a Drier, Hotter and More Crowded Future

Nearly 44 per cent of the population in the Horn of Africa is already subject to extreme food shortages. What will happen if the population continues to grow and climate change exacerbates the harsh conditions?

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The Amazon is widely considered to be one of the world's most important natural areas and a high priority for conservation. Its importance to the global carbon cycle makes understanding its response to drought essential to modeling of the planet's future.

ThumbnailGeoengineering to Combat Global Warming

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The Athabasca Oil Sands region of Alberta, Canada forms the second-largest deposit of recoverable oil in the world after Saudi Arabia (Whitfield and others 2010). The energy and environmental costs of extracting oil from oil sands have made their development very controversial. The oil sands industr...

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ThumbnailHuge Iceberg Breaks off Greenland's Petermann Glacier

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ThumbnailGreening Cement Production has a Big Role to Play in Reducing Greenhouse Gas Emissions

Next to water, concrete is the second-most consumed substance on earth; on average, each person uses nearly three tonnes a year. Portland cement, the major component of concrete, is used to bind the materials that make up concrete. The concrete industry uses about 1.6 billion tonnes of portland ceme...

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As confirmed by the impacts of the December 2004 Asian tsunami and Hurricane Katrina in 2005, intact mangroves help stabilize shorelines and thus protect lives and property from such natural disasters. They also provide other ecosystem services, such as breeding and nursing grounds for marine specie...

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