Tuesday, 11 July 2017

Increasingly-dire headlines on abrupt climate change

Five years or so ago when I started thisblog there was very little in the mainstream about climate change. Now the media is often dominated by increasingly dire headlines

Goodbye cruel world: we’ve passed the carbon tipping point

We have passed a grim new milestone for atmospheric carbon dioxide levels, probably for good. Earlier this week Mauna Loa Observatory, a key site for keeping tabs on carbon dioxide measured 400 parts per million — a figure that some researchers have claimed would be the critical tipping point for the Earth.

Numbers higher than 400 ppm have been observed a few times in the last decade, what makes this significant is that September is usually the month when global C02 levels are at the lowest.

Ralph Keeling, a scientist at the Scripps Institute for Oceanography and lead on their CO2 monitoring program wrote that it was “almost impossible” that we will drop below 400 ppm in the coming months. “Brief excursions toward lower values are still possible, but it already seems safe to conclude that we won’t be seeing a monthly value below 400 ppm this year – or ever again for the indefinite future.”

I won’t waste time debating whether or not global climate change is a thing. The overwhelming majority of scientists and researchers that cover climatologic and atmospheric science support the theory. It’s also one of the best-supported theories in the whole of science. That said, what happens next isn’t completely clear.

We know, for example, that the Earth has a lot of feedback loops that can (and have) caused runaway climate change in the past. For example, when global temperatures cross certain thresholds, they trigger other effects that accelerate warming. So far, the consensus is that the oceans have taken the biggest hit, absorbing the majority of the temperature increase. They’re dark and absorb more of the sun’s heat than the ice caps, plus ocean currents can shift excess heat all around — something the hard and rocky crust can’t. But, that time may be coming to a close soon. As our planet continues to warm, more and more ice will melt. That’s really bad news. The ice caps are reflective and bounce a lot of extra heat back out into space. As they melt and become oceans, they’ll absorb more heat and melt, even more, ice. That’s just one potential scenario, but it’s emblematic of what we face as a species.


We still may not see major effects for another few years, and that’s part of the problem. Any major potential solutions have to be started now. Options like new nuclear power plants can take ten years or more to build. It’s possible that crossing this threshold will scare more people into action, and help more nations to commit to lowering carbon emissions.

The Paris Agreement is the first and largest step towards stopping the actual, literal apocalypse. So far more than 60 nations have agreed to the international resolution to dramatically cut carbon emissions. But together they make up just shy of 50% of global carbon output. The US, China, and loads of other major, industrialized countries need to commit to working together on one massive global project to save life on Earth. It won’t be easy; it will cost trillions and trillions of dollars, but it’ll be the best investment we can possibly make.

Not cutting emissions will cost many, many times more than building out the infrastructure we need right now, especially as rising sea levels, depletion of marine life, etc. force us to find new homes and sources of food.

I urge you: talk to your friends. Talk to your family. Talk to anyone who will listen. Call politicians. Send letters. Get ahold of the biggest decision makers you can and encourage them to commit to change and talk to their colleagues. There is still time, but we are running out… and fast.

Chronicles of the climate crisis.

Meanwhile, back on Earth One, we're all pretty well bloody doomed. From New York Magazine:

when it comes to contemplating real-world warming dangers, we suffer from an incredible failure of imagination. The reasons for that are many: the timid language of scientific probabilities, which the climatologist James Hansen once called "scientific reticence" in a paper chastising scientists for editing their own observations so conscientiously that they failed to communicate how dire the threat really was; the fact that the country is dominated by a group of technocrats who believe any problem can be solved and an opposing culture that doesn't even see warming as a problem worth addressing; the way that climate denialism has made scientists even more cautious in offering speculative warnings; the simple speed of change and, also, its slowness, such that we are only seeing effects now of warming from decades past; our uncertainty about uncertainty, which the climate writer Naomi Oreskes in particular has suggested stops us from preparing as though anything worse than a median outcome were even possible; the way we assume climate change will hit hardest elsewhere, not everywhere; the smallness (two degrees) and largeness (1.8 trillion tons) and abstractness (400 parts per million) of the numbers; the discomfort of considering a problem that is very difficult, if not impossible, to solve; the altogether incomprehensible scale of that problem, which amounts to the prospect of our own annihilation; simple fear. But aversion arising from fear is a form of denial, too.

The piece couldn't be more apocalyptic if the author were writing in a cave on Patmos. Miami and Bangladesh, gone within a century. New York rendered uninhabitable by heat. Millions of refugees, all of them starving, because of massive food shortages.

Warming beyond 2 ºC could send the region's forests moving north, and cause extensive drying.

Seville and Lisbon have thrived for more than a thousand years in a temperate climate. But if global warming continues at the current pace, these cities will be in the middle of a desert by the end of the century, climate modellers report on 27 October in Science.

Maintaining the historic ranges of the region’s ecosystems would require limiting warming to just 1.5 ºC, by making substantial cuts to the world’s greenhouse-gas emissions, the analysis concludes. Otherwise, the vegetation and ecosystems of the Mediterranean basin will shift as temperatures rise. Increasing desertification in southern Europe is just one of the changes that would result.

Planet could heat up far more than hoped as new work shows temperature rises measured over recent decades don’t fully reflect global warming already in the pipeline

How much global temperatures rise for a certain level of carbon emissions is called climate sensitivity and is seen as the single most important measure of climate change. Computer models have long indicated a high level of sensitivity, up to 4.5C for a doubling of CO2 in the atmosphere.

However in recent years estimates of climate sensitivity based on historical temperature records from the past century or so have suggested the response might be no more than 3C. This would mean the planet could be kept safe with lower cuts in emissions, which are easier to achieve.

But the new work, using both models and paleoclimate data from warming periods in the Earth’s past, shows that the historical temperature measurements do not reveal the slow heating of the planet’s oceans that takes place for decades or centuries after CO2 has been added to the atmosphere.

The vast majority of child migrants uprooted by violence, poverty and climate change remain in Africa, write UNICEF's Lachlan Forsyth and Patrick Rose

The vast majority of child migrants uprooted by violence, poverty and climate change remain in Africa, according to a new report by child rights organisation UNICEF.

It is a bitter irony that the countries that have done the least to cause climate change are going to suffer the most. Countries that have minuscule carbon footprints are going to be the first to suffer the consequences of flooding, drought and displacement.

In West and Central Africa, the impact of climate change will be especially severe, with the region set to experience a 3 to 4 degree rise in temperature this century – more than one and a half times higher than anywhere else on the planet.

For the millions of people living in this vast region, longer droughts and intense storms will make farming and herding more difficult, and people will be forced to seek a better life.

Already, children account for more than half of the 12 million West and Central African people on the move each year. Contrary to many opinions, 75 percent of them remain in sub-Saharan Africa, with fewer than one in five heading to Europe.

This current wave of migrants is just the start of a swelling humanitarian crisis. Migration involving children and young people is likely to increase due to rapid population growth and urbanisation, climate change, inequitable economic development, and persistent conflict.

Poverty is a powerful driver of migration in West and Central Africa. Countries with high levels of poverty are more likely to be a source of migration as people look to improve their lot in life. In interviews conducted by UNICEF, migrants describe the feeling of ‘having nothing to lose,’ aware that by migrating they are taking a risk, but it is a gamble that might pay off

Researchers talk of ‘biological annihilation’ as new study reveals that billions of populations of animals have been lost in recent decades

A “biological annihilation” of wildlife in recent decades means a sixth mass extinction in Earth’s history is already well underway and is more severe than previously feared, according to new research.

Scientists analysed both common and rare species and found billions of regional or local populations have been lost. They blame human overpopulation and overconsumption for the crisis and warn that it threatens the survival of human civilisation, although there remains a short window of time in which to act.

The new study, published in the peer-reviewed journal Proceedings of the National Academy of Sciences, eschews the normally sober tone of scientific papers and calls the massive loss of wildlife a “biological annihilation” that represents a “frightening assault on the foundations of human civilisation”.

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