Chemistry World Blog

Scientists are celebrating – it’s the 25th anniversary of the discovery of a hole in the ozone layer above the Antarctic. A strange cause for celebration you may think, but as the ozone layer protects us from 90 per cent of the sun’s ultraviolet rays, we could be a lot hotter if it had gone undetected!

— ozone_depletion1

In 1985, Joseph Farman, Brian Gardiner and Jonathan Shanklin, reported that the amount of ozone seen in the spring above the Antarctic had declined significantly year-on-year since the late 1970s. They linked this depletion in ozone to the use of industrial solvents and a rise in the use of chlorofluorocarbons (CFCs) as refrigerants and propellants and their subsequent release into the atmosphere.

The Montreal Protocol in 1987, as well as support from chemical manufacturers and the public, led to the phasing out of CFCs, halons and carbon tetrachloride by 2000, and methyl chloroform by 2005. It is predicted that if the Montreal Protocol restrictions are followed, Antarctic springtime ozone levels could return to 1950s levels by 2080. The subsequent reduction in CFCs has also had a positive effect on climate change as they are potent greenhouse gases.

Mike Brown

— aaas

Well here I am in sunny San Diego, attending the 2010 meeting of the American Association for the Advancement of Science (AAAS). Jet-lag finally conquered, I thought I’d let you know a bit about what’s been going on here. (more…)

Well, the biggest ever conference on climate change has come to an end – and the messages are certainly mixed. Leaders of developed countries are hailing the result as a positive step, but many see the accord as a disappointment.

Here are the headlines, but look out for an in-depth roundup on the Chemistry World website early in the new year.

(more…)

— time-is-running-out1

Leaked documents, walk-outs, gate-crashes…there’s been high drama at the Copenhagen climate summit, but has there actually been any progress towards saving the planet?

Increasingly concerned voices would suggest not, or at least not enough. World leaders will be landing in Denmark later this week for the crunch talks towards the end of the summit (that is, if they can get in. Word is that logistical screw-ups have left hundreds of delegates – including ministers – stranded in the snow outside waiting for hours before being admitted). (more…)

A new report presented yesterday at the Copenhagen climate conference ranked 30 of the continent’s financial capitals according to the European Green City Index (see top ten green cities below). This index is an indicator of a city’s environmental performance and is measured against eight categories: CO₂ emissions, energy, buildings, transport, water, waste and land use, air quality and environmental governance. (more…)

— global-warming

The United Nations Climate Change Conference (or just ‘Copenhagen’, as it’s affectionately come to be known) officially kicked off today.

192 nations and over 100 heads of states and government from around the world will be in attendance during the two-week summit, the events of which will be covered by 5,000 journalists. So it shouldn’t be too hard to keep abreast of what’s going on. (more…)

— lobster

Scientists had always assumed that increased levels of CO₂ in marine systems would lead to decalcification of shell-building creatures such as crabs or lobsters. They had worked out that ocean acidification occurs because atmospheric CO₂ is taken up as carbonic acid, which is then neutralised by existing carbonate ions and trapped as bicarbonate, a process that ultimately causes a decline in oceanic pH.

So far so good, but how does this affect shell growth? Well, shells are made out of calcium carbonate and the said organisms utilise free carbonate to build this up so, in a nutshell – excuse the pun – the lower the concentration of carbonate ions, the less likely these organisms will be to produce their structures faster than they are eroded by natural processes. (more…)

— global-warming-freezing

One week until the conflab in Copenhagen, and China and the US have finally put some numbers on the table, but fresh reports of friction from developing nations could put a dampener on the news.

They might not be quite the numbers some were hoping for, but it’s a start. Last week President Obama pledged that the US will cut its emissions ‘in the range of’ 17 per cent below 2005 levels by 2020 (that’s about 3 per cent below 1990 levels) and 83 per cent by 2050. (more…)

If the politicians didn’t already have enough reasons to take the Copenhagen climate summit seriously, then Marshall Burke, from the University of California at Berkeley, has possibly given them one more.

Writing in the Proceedings of the National Academy of Sciences, Burke and colleagues suggest that armed conflict in sub-Saharan Africa can be linked to variations in temperature – with substantial increases in conflict during warmer years. (more…)

— hot-earth

Good news this week as the US has stood up and said it might just manage to put forward an emission reduction target in time for the Copenhagen climate conference after all.

The announcement, apparently made by an unnamed White House official, came following promising reports that over 60 presidents and prime ministers will now be attending the conference in person, boosting hopes that an agreement will be made. (more…)