By Roger Harrabin (Follow Roger on Twitter @rharrabin)
Environment analyst, BBC News

The Arctic seas are being made rapidly more acidic by carbon dioxide emissions, according to a new report.

Scientists from the Arctic Monitoring and Assessment Programme (AMAP) monitored widespread changes in ocean chemistry in the region.

They say even if CO2 emissions stopped now, it would take tens of thousands of years for Arctic Ocean chemistry to revert to pre-industrial levels.

Many creatures, including commercially valuable fish, could be affected.

They forecast major changes in the marine ecosystem, but say there is huge uncertainty over what those changes will be.

It is well known that CO2 warms the planet, but less well-known that it also makes the alkaline seas more acidic when it is absorbed from the air.

Absorption is particularly fast in cold water so the Arctic is especially susceptible, and the recent decreases in summer sea ice have exposed more sea surface to atmospheric CO2.

The Arctic’s vulnerability is exacerbated by increasing flows of freshwater from rivers and melting land ice, as freshwater is less effective at chemically neutralising the acidifying effects of CO2.

The researchers say the Nordic Seas are acidifying over a wide range of depths – most quickly in surface waters and more slowly in deep waters.

The report’s chairman, Richard Bellerby from the Norwegian Institute for Water Research, told BBC News that they had mapped a mosaic of different levels of pH across the region, with the scale of change largely determined by the local intake of freshwater.

“Large rivers flow into the Arctic, which has an enormous catchment for its size,” he said.

“There’s slow mixing so in effect we get a sort of freshwater lens on the top of the sea in some places, and freshwater lowers the concentration of ions that buffers pH change. The sea ice has been a lid on the Arctic, so the loss of ice is allowing fast uptake of CO2.”

This is being made worse, he said, by organic carbon running off the land – a secondary effect of regional warming.

“Continued rapid change is a certainty,” he said.
“We have already passed critical thresholds. Even if we stop emissions now, acidification will last tens of thousands of years. It is a very big experiment.”

The research team monitored decreases in seawater pH of about 0.02 per decade since the late 1960s in the Iceland and Barents seas.

Chemical effects related to acidification have also been encountered in surface waters of the Bering Strait and the Canada Basin of the central Arctic Ocean.

Scientists estimate that the average acidity of surface ocean waters worldwide is now about 30% higher than before the Industrial Revolution.

The researchers say there is likely to be major change to the Arctic marine ecosystem as a result. Some key prey species like sea butterflies may be harmed. Other species may thrive. Adult fish look likely to be fairly resilient but the development of fish eggs might be harmed. It is too soon to tell.

Thanks to the BBC

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If you love our oceans and the creatures in them check out this amazing underwater clip. It’s from our Before It’s Too Late series, episode Whale Shark – Gypsy of the Deep. Shot by Richard Todd.

Glaciers in the east and central regions of the Hindu Kush-Himalaya (HKH) region are retreating at an alarming rate according to a new report released this week by the National Research Council.  While the glaciers in the western HKH appear to be stable and possibly growing, glaciers over the rest of the HKH are melting at rates similar to the collapsing glaciers in much of the rest of the world.

Warming is particularly acute at higher elevations of the Himalayas and Tibetan Plateau, which over the past fifty years have warmed at three times the global average.

The report, which analyzes current scientific knowledge about the glaciers in the HKH region and impacts on water resources, notes that glacier melt provides needed water during extreme weather events such as droughts, acting as a ‘buffer’ when water needs are more desperate, although it found that the melt is not likely to significantly impact water resources in the near-term at low elevations where rains and snow-melt are more important.  The glaciers are the headwaters for rivers that provide fresh water and irrigation for as many as 1.5 billion people in Asia.

“The number of disastrous droughts and extreme temperature events in Asia have more than doubled over the past twenty years and they are only expected to increase as climate change gets worse,” stated Durwood Zaelke, President of the Institute for Governance and Sustainable Development. “This report underscores the  need to take fast action to protect this critical region including rapid reductions of short-lived climate pollutants particularly black carbon.”

The report cautions that the causes for glacier melt are complex but are driven in large part by rising temperatures. Aerosols such as black carbon and desert dust are also significant contributors to warming in the region.

Another recent report on black carbon in the Brahmaputra River Valley, southeast of the Tibetan Plateau, found that the exceptionally high concentrations of black carbon in the area contributed to the extreme regional climate change, including increased surface temperature and changing precipitation patterns.  Black carbon may be responsible for up to 1°C of warming in the HKH region.

Cutting black carbon in addition to other short-lived climate pollutants such as methane, tropospheric ozone, and hydrofluorocarbons (HFCs) can reduce the current rate of global warming by almost half, the rate of warming in the Arctic by two-thirds, and the HKH region by half for the next 30 or more years while avoiding up to 4.7 million premature deaths each year from outdoor air pollution and up to 1.6 million a year from indoor pollution.

Black carbon is targeted by the new Climate and Clean Air Coalition to Reduce Short-Lived Climate Pollutants, along with HFC and methane. There are currently 27 members of the Coalition including the G8 countries, the European Commission, World Bank, and the United Nations Environment Programme, which will host the Secretariat.

“The Climate and Clean Air Coalition may be the only way to reduce climate impacts in the near term, and is a critical complement to the primary battle to reduce emissions of CO₂,” said Zaelke. “We need to take fast-action.”

The NRC Report can be found here.

Contact: Nathan Borgford-Parnell: +1.202.338.1300, nborgford-parnell@igsd.org