Monday, December 07, 2015

Wise words rise from climate disasters

COP21: Planning and preparation can lessen the heavy human toll of natural disasters linked to climate change, survivors tell UN summit delegates.

By Tim Radford

[PARIS, 7 December, 2015] More than half a million people have perished in 15,000 climate-related disasters since 1995, at a cost of $US2.97 trillion, according to new statistics released during the COP21 climate summit.

This is the second such tally of devastation and death accumulated since COP1, the first meeting two decades ago of world governments to confront the challenge of climate change.

That the latest Global Climate Risk Index, compiled by the organisation Germanwatch, differs from the UN’s own recent estimates over the same two decades is partly because compilers used different approaches and criteria, partly an indicator of the innate difficulties of linking sustained suffering and loss to discrete meteorological events, and partly because Germanwatch does not include all the statistics from slowly-emerging events such as drought.

But both sets of figures confirm that as global temperatures creep ever higher, as a consequence of greater concentrations of greenhouse gases in the atmosphere, in turn because of human activity, extreme events present ever greater hazards in the form of storms, hail, tornadoes, storm surges, floods, landslides, ice storms, wildfires and droughts.

In 2014, the worst three affected countries were Serbia – hit by catastrophic floods that swept through southeast Europe that year – Afghanistan and Bosnia-Herzegovina. The three worst affected countries over the two decades are Honduras, Myanmar and Haiti, with the Philippines in fourth place, just above Nicaragua and Bangladesh.

Lower target

The Philippines, a vast archipelago of 7,000 large and small islands, is in the path of around 20 to 25 typhoons a year that increasingly hit communities that had once considered themselves relatively safe. The 190 nations attending COP21 have committed themselves to containing global warming to an average of 2°C above pre-industrial levels, but the Philippines is one of a large group that would prefer the world to aim for 1.5°C.

Tropical cyclones are linked to sea surface temperatures and could become more intense, more frequent or more extensive as temperatures rise, and tropical countries with vast coastlines are inevitably more likely to be in the path of the coming storms.

But the nations most at hazard have, under a UN umbrella programme, also been trying to anticipate the worst. And COP21 delegates heard that the Philippines government, for the first time, has started to keep tally not just of the statistics of catastrophe, but also of the disasters that did not happen.

Attitudes to hazard have changed. What had once been the country’s national disaster agency co-ordinating council is now a national disaster risk management council.
Raymund Liboro, the Philippines assistant secretary for climate change and disaster risk reduction, told the conference: “While we consider ourselves as vulnerable, we do not consider ourselves helpless.”

One case in point was Typhoon Koppu, the thirteenth tropical cyclone to hit the nation in 2015. Winds reached 240 km an hour, prodigious quantities of rain were dumped on the hills, and in one region more than 1,000 millimetres of rain fell in 24 hours. It triggered a huge flow of debris that buried three townships.

Communities saved

In 2012, during a similar storm, more than 1,000 people died. But although Typhoon Koppu in October dislodged 41 million cubic metres of rock, rubble and forest from the mountainsides, it killed nobody. Forewarned, the authorities had evacuated all three communities and saved 7,000 families.

So the climate risk index and other sources of information served not just as a league table of human suffering, but also as an indicator of levels of future risk and a reminder that meteorological hazard now bears the fingerprint of climate change.

With good information, Mr Liboro said, countries could begin to cope, mitigate, adapt and survive. “Behind those numbers are actual lives,” he said. “We consider ourselves already survivors of climate change, and survivors have stories to tell.” 

– Climate News Network

Sunday, December 06, 2015

Scientists post extreme weather warning

COP21: Climate change means that temperate Europe faces the twin threat of life-threatening heatwaves and periods of bitter cold over the next 20 years.

By Tim Radford

[PARIS, 6 December, 2015] – New research warns that longer, hotter and more frequent heatwaves than those that killed 55,000 Russians in 2010, or 72,000 in France, Portugal, Italy, the Netherlands, Germany and the UK in 2003, will hit Europe in the next two decades.

But, over the same period, Europe could also begin to get colder as a consequence of a drop in solar activity, and a century-long chill could be on the way, according to a study of long-period climate cycles.

And if global warming accelerates, and average global ocean temperatures rise by 6°C or more, most of the living, breathing world could in any case begin to suffocate, according to ominous calculations by a mathematician. At some point, the providers of oxygen could begin to perish.

All three uncomfortable projections were published as 30,000 delegates, politicians, observers, pressure groups, and journalists gathered in Paris for COP21, the UN summit on climate change, which is meeting to try to forge an agreement that could, ultimately, limit global warming to a planetary average of 2°C or less.

Magnitude index

Simone Russo, a geophysicist, and colleagues from the European Union Joint Research Centre at Ispra in Italy report in Environmental Research Letters that they developed a heatwave magnitude index to cope with a problem once considered improbable for temperate Europe − extremes of heat.

The index is a tool for statistical analysis, and provides a way of matching bygone events with possible future extremes. Deaths in Europe accounted for 90% of global mortality from heat extremes in the last 20 years. And there could be more on the way.

“Even if global mean temperatures don’t increase too much, we’ll see more extreme events,” Dr Russo says. “These will be hotter, longer and more frequent.”

Scientists from universities in Northumbria, Hull and Bradford in the UK, and from Lomonosov State University in Moscow, are not so sure. Their study in Scientific Reports journal examines the rhythms of the sun, and foresees a possible minimum in solar magnetic activity, which has in the past been linked to extended cold periods in the Earth’s climate history.

The latest research tries to reconstruct climate from 1200 AD and make a forecast until the year 3200, based ultimately on the count of sunspots. And the scientists think a new low is about to begin.

“Studies have shown that, over the last 400,000 years, there were five global warming and four ice ages,” says Elena Popova, a physicist at Lomonosov Moscow State University. “What caused them? How much can solar activity affect the weather and climate change?
This question is still not solved and is an extremely relevant and interesting challenge for the various researchers around the world.”

Not everyone sees a clear link between sunspot numbers and periodic swings in global temperature. But there isn’t much argument about the importance of plants in the generation of the oxygen for the rest of creation − and an estimated two-thirds of this comes from phytoplankton in the oceans, which cover 70% of the globe.

Ocean productivity

“The rate of oxygen production depends on water temperature and hence can be affected by the global warming,”, say Sergei Petrovskii, professor of applied mathematics, and colleagues at the University of Leicester, UK, in the Bulletin of Mathematical Biology.

The scientists made a mathematical model of the processes that control ocean productivity, and then added higher levels of warming. Were ocean temperatures to rise by an average of 6°C by 2100, the increase would start to disrupt the process of photosynthesis.

Right now, this is a less than likely outcome: 184 of the 190 nations now engaged in the COP21 summit have submitted pledges to reduce the carbon dioxide emissions that generate greenhouse gases and drive global warming, and the latest forecast is that, were all these pledges honoured, global warming could perhaps be contained to within 3°C.

If these were improved upon – and that, too, is the ambition behind the climate summit – then the warming could be limited to 2°C. But the predictions of the Leicester team are a reminder of the high price of failure.

They warn: “Our results indicate that the depletion of atmospheric oxygen on a global scale (which, if it happens, obviously can kill most of the life on Earth) is another possible catastrophic consequence of global warming, a global ecological disaster that has been overlooked.”

 – Climate News Network