Sunday, May 03, 2020
Melting ice sheets in Antarctica and Greenland are responsible for a global sea level rise of 0.55 inches since 2003, study shows
Ho-hum. The accuracy of measurement of these surveys is very uncertain. And even if it were, what caused the melting? Note that global warming is not mentioned. The probable cause is the well-known subsurface volcanic activity at both poles
Ice sheets in Antarctica and Greenland shrinking and melting since 2003 have contributed towards a global sea level rise, a NASA funded study revealed.
Researchers at the University of Washington examined data from two space lasers that were able to make the most precise measurements of the ice sheets to date.
They found the net loss of ice from Antarctica, along with Greenland's shrinking ice sheet, has been responsible for 0.55 inches of sea level rise since 2003.
In Antarctica, sea level rise is driven by the loss of the floating ice shelves melting in a warming ocean - they hold back the flow of land-based ice into the ocean.
The study found that Greenland's ice sheet lost an average of 200 gigatons of ice per year, and Antarctica's ice sheet lost an average of 118 gigatons of ice per year.
One gigaton of ice is enough to fill 400,000 Olympic-sized swimming pools.
The findings come from the Ice, Cloud and land Elevation Satellite 2 (ICESat-2), which was launched into orbit in the autumn of 2018.
The team behind the study compared recent ICESat-2 data to measurements from its predecessor taken between 2003 and 2009.
'If you watch a glacier or ice sheet for a month, or a year, you're not going to learn much about what the climate is doing to it,' said lead author Benjamin Smith.
'We now have a 16-year span between ICESat and ICESat-2 and can be much more confident that the changes we're seeing in the ice have to do with the long-term changes in the climate,' said the glaciologist at the University of Washington.
'We're seeing high-quality measurements that carpet both ice sheets, which let us make a detailed and precise comparison with the ICESat data.'
Previous studies of ice loss or gain often analyse data from multiple satellites and airborne missions but the new study takes just a single type of measurement.
It takes height as measured by an instrument that bounces laser pulses off the ice surface - providing the most detailed and accurate picture of ice sheet change.
The researchers took elements of earlier ICESat measurements and overlaid the new data from ICESat-2 measurements taken last year.
They then ran the data through computer programs that accounted for the snow density and other factors, and then calculated the mass of ice lost or gained.
'The new analysis reveals the ice sheets' response to changes in climate with unprecedented detail, revealing clues as to why and how the ice sheets are reacting the way they are', said co-author Alex Gardner, a NASA glaciologist
Of the sea level rise that resulted from ice sheet meltwater and iceberg calving, about two-thirds of it came Greenland, the other third from Antarctica
'It was amazing to see how good the ICESat-2 data looked, right out of the gate,' said co-author Tom Neumann, the ICESat-2 project scientist.
'These first results looking at land ice confirm the consensus from other research groups, but they also let us look at the details of change in individual glaciers and ice shelves at the same time,' Neumann said.
In Greenland, there was a significant amount of thinning of coastal glaciers.
The Kangerdulgssuaq and Jakobshavn glaciers, for example, have lost 14 to 20 feet of height per year for the past 16 years - the authors discovered.
Warmer summer temperatures have melted ice from the surface of the glaciers and ice sheets, and in some places warmer ocean water erodes away the ice at their fronts,' the NASA backed team say.
In Antarctica measurements showed that the ice sheet is getting thicker in parts of the continent's interior, likely as a result of increased snowfall, Smith said.
The loss of ice from the continent's margins, especially in West Antarctica and the Antarctic Peninsula, far outweighs any gains in the interior.
'In West Antarctica, we're seeing a lot of glaciers thinning very rapidly,' Smith said.
'There are ice shelves at the downstream end of those glaciers, floating on water. And those ice shelves are thinning, letting more ice flow out into the ocean as the warmer water erodes the ice.'
These ice shelves, which rise and fall with the tides, can be difficult to measure, said co-author Helen Amanda Fricker, a glaciologist at Scripps Institution of Oceanography at the University of California, San Diego.
Some of them have rough surfaces, with crevasses and ridges, but the precision and high resolution of ICESat-2 allows researchers to measure overall changes, without worrying about these features skewing the results.
This is one of the first times that researchers have measured loss of the floating ice shelves around Antarctica simultaneously with loss of the continent's ice sheet.
Ice that melts from ice shelves doesn't raise sea levels, since it's already floating - just like an ice cube in a full cup of water doesn't overflow the glass.
But the ice shelves do provide stability for the glaciers and ice sheets behind them -'It's like an architectural buttress that holds up a cathedral,' Fricker said.
'If you take away the shelves, or even if you thin them, you're reducing that buttressing force, so the grounded ice can flow faster.'
The researchers found ice shelves in West Antarctica, where many of the continent's fastest-moving glaciers are located, are losing mass.
Patterns of thinning show that Thwaites and Crosson ice shelves have thinned the most, an average of about five meters (16 feet) and three meters (10 feet) of ice per year, respectively,' the researchers said.
This NASA funded study has been published in the journal Science.
SOURCE
'Lockdown is FASCIST': Elon Musk demands that people are given 'back their God-damn freedom' after his California Tesla plant is shut for another MONTH
He's right
Tesla Inc CEO Elon Musk on Wednesday called sweeping US stay-at-home restrictions to curtail the coronavirus outbreak 'fascist' as the electric carmaker posted its third quarterly profit in a row.
Shares of the company were up more than 9% at $873 in extended trade and Tesla's report of a profitable quarter came just a day after Detroit-based rival Ford Motor Co reported a $2 billion first-quarter loss and forecast losing another $5 billion in the current quarter.
But one of the biggest disruptions to Tesla has been the government-ordered shutdown of its factory in Fremont, California March 24.
Alameda County, where the factory is based, on Wednesday extended stay-at-home orders until May 31 and vehicle manufacturing is not considered an essential business that is exempt.
'To say that they cannot leave their house and they will be arrested if they do, this is fascist,' Musk said on an earning calls Wednesday
On a conference call on Wednesday, Musk said he did not know when they could resume production.
'I think the people are going to be very angry about this and are very angry,' Musk said as he went off track in the call about earnings. 'It’s like somebody should be, if somebody wants to stay in the house that’s great, they should be allowed to stay in the house and they should not be compelled to leave.
'To say that they cannot leave their house and they will be arrested if they do, this is fascist. This is not democratic, this is not freedom. Give people back their goddamn freedom!'
The strictest stay-at-home orders recommend that people only leave their homes for essential trips such as visiting the grocery store or pharmacy.
Tesla shut down the California factory just as it was ramping up production of its new electric crossover utility vehicle Model Y, which it expects to generate record demand and higher profit margins.
Tesla on Wednesday said the Model Y was already contributing profits, marking the first time in the company's history that a new vehicle is profitable in its first quarter.
Earlier this month, Tesla said production and deliveries of its Model Y sports utility vehicle were significantly ahead of schedule, as it delivered the highest number of vehicles in any first quarter to date, despite the outbreak.
Tesla reported that it eked out a first-quarter net profit Wednesday. The electric car and solar panel company said it made $16 million from January through March, its third-straight profitable quarter.
But Musk called the state stay-at-home order a 'serious risk' to the business.
'So the expansion of the shelter in place or as frankly I would call it, forcibly imprisoning people in their homes, against all their constitutional rights, is my opinion, and breaking people’s freedoms in ways that are horrible and wrong, and not why people came to America or built this country, excuse me,' Musk added later.
'It’s an outrage. It will cause loss, great, great harm, but not just to Tesla, but any company. And while Tesla will weather the storm there are many small companies that will not.'
SOURCE
The madness of Brian Cox
Brian Cox, the softly spoken TV professor and former keyboard player for D:Ream, has found a ‘silver lining’ to the coronavirus crisis.
Appearing on Good Morning Britain yesterday to mark Earth Day, Cox said that the coronavirus crisis has ‘shown us what a future with less pollution and more active wildlife could be like’.
It is certainly true that emissions have enormously declined over the past few months. And for Cox, coronavirus ‘could change how we think about our impact on the environment’ because it has revealed what a world looks like ‘with lower pollution’ and ‘without aircraft flying overhead’. This is a ‘future we could choose’, he says.
Of course, all it took to bring about this reduction in emissions was a novel virus that has ravaged the world, killing hundreds of thousands of people, and a political response to this crisis that has put billions of people under house arrest and sent the global economy into free fall. We have no idea how devastating the economic, social and political fallout could yet be.
So, has Cox lost his mind? Environmentalists have always been cavalier about the human costs of their desire to rein in economic progress for the supposed good of the planet. But this is surely a new low.
SOURCE
"The science" and "the experts" are no longer sacrosanct
Here are some words you would never have expected to read in the Guardian. Boris Johnson’s government, the paper says, is using the refrain ‘following the science’ to ‘abdicate responsibility for political decisions’. It reports some experts’ concerns that in constantly saying ‘we are following scientific advice on Covid-19’, ministers are ‘abdicating political duty to [a] narrow field of opaque expertise’. In short, the cabinet is too faithfully traipsing in the wake of scientific expertise rather than making judgements about what might be the best course for the country in the era of Covid. The Guardian says there is now worry among scientists themselves that the current ‘prominence given to science in supporting political decisions risks burdening scientists with unrealistic expectations’.
This is a turnaround of epic proportions. The Guardian has probably done more than any other media outlet to push the new orthodoxy that political decision-making must be expert-led and scientifically infused. On everything from climate change to a No Deal Brexit, the liberal elite’s mantra in recent years has been ‘Listen to The Science’ or ‘Listen to The Experts’. The Science – they always say ‘the science’ rather than just ‘science’, to give it an extra godly quality – has been turned into a kind of gospel truth we must all bow down to, and upon which all political decisions must be based. Indeed, for the past year we have had Greta Thunberg, feverishly promoted by the political establishment and media class, touring the world and demanding we all ‘listen to The Science’.
Now, it seems, this latter-day demand for unflinching fealty to an implacable truth – though in this case derived from science rather than from God – is being called into question in some quarters. It has dawned on people that science is a complex, drawn-out, falsifiable search for solutions and truths, not a dispenser of unquestionable wisdom that entire societies must organise themselves around. The Spectator reports that ‘cabinet members have been taken aback by the disagreements among those now advising the government’. One cabinet member says ‘scientists are as bitchy as a bunch of lawyers’. Another says that even the scientists who make up the Scientific Advisory Group for Emergencies – which has effectively become the supreme governing body of the UK – ‘don’t agree with each other’. ‘They bicker’, apparently, which is not at all surprising: science is an often conflictual process of expanding our understanding of the natural world, not a font of unimpeachable political or moral wisdom.
The cabinet member said to the Spectator: ‘And we talk about following “the science” as if there is one opinion and not at least seven.’ This is a critical point and one that must endure even after the Covid-19 crisis. Science is not a good guide for society. Of course science is essential to our understanding of the world and to the creation of the new insights, technologies and treatments our societies need. But it cannot tell us what is best for our societies in political, moral or economic terms. Indeed, it is the very specialised nature of science, whereby very clever people remove themselves from normal life and focus on one field for a very long period of time, that makes it unsuited to the broader, democratic question of what is in the best interests of society. When science becomes infused with politics, both suffer: science risks becoming politicised while democratic life is weakened through a growing reliance on ‘expert advice’ over the considerations and wisdom of the crowd.
What the Covid-19 crisis has really done is throw the science question into sharp relief. In the eyes of those of us who understand the importance of democratic leadership and the necessity of specialised science, there has always been a problem with using science to justify political action and moral conviction. But now, because of the intensity of the current crisis, others appear to be realising that, too. Epidemiologists might understand how viruses tend to spread, but their understanding of the dire economic consequences of a lockdown is no better than anyone else’s, some are saying. Modelling might be a useful source of information for politicians, but to partake in an unprecedented demobilisation of working people and economic life on the basis of a model is ridiculous and dangerous, others are saying.
This is all good, if a little late. But we need to push further now. One of the key dynamics in the politicised elevation of science and expertise in recent years has been the crisis of politics and institutions, and in particular the crisis of leadership. Science has slowly filled the gap where political and moral judgement ought to be. In the Covid-19 crisis, one of the most striking things has been the relative ease with which the government has abdicated its judgement in favour of following the science or succumbing to media pressure and to supposed public opinion. It speaks to a political class that lacks the capacity for leadership, and in particular lacks leadership’s most important virtue: courage.
This is not Boris-bashing. There is no more infantile political pursuit in the UK right now than Boris-bashing. It is ahistorical to pin the blame for the decades-long sclerotic nature of the British bureaucracy on a man who has been PM for eight months, and it is immoral to blame deaths from Covid-19 on him too, as if a novel virus could be stopped in its tracks by political decision-making alone. Will Boris also be culpable for this year’s flu deaths? That would be ridiculous. No, this is a call for a broader reorientation of political life, away from the caution and instinct for self-preservation that has defined it for a few decades now, and which has fuelled its reliance on the authority of science and experts, and towards a new and meaningful era of leadership in which our leaders take seriously their responsibility to make judgements, take decisions, and convince the rest of us, intellectually and democratically, that it is the right course of action.
It is now widely reported that Boris’s government hasn’t only been ‘following the science’ but has also felt under incredible pressure to buckle to the media class’s demand for action, in particular for a lockdown, and to ‘public opinion’ that says the lockdown is the right thing. There is no doubting the corrosive role the media are playing right now, and have been for many years in fact. Their increasingly opinionated, moralised coverage of the news, in which they seem to think their role is to harry and shame people in power rather than to report on what is happening, has led to a dangerous culture of media self-importance. Politicians, already feeling uncertain of their authority, too often feel cowed by the newly arrogant, agenda-defining media, and are reluctant to fall foul of their demands and diktats. If it is true that Boris put the country into lockdown partly in response to media pressure, then the media themselves may have a lot of questions to answer about the damage currently being done by this unprecedented freeze on working life and the economy.
As to the question of ‘public opinion’ – this needs to be put into context. Polls currently show fairly widespread support for the lockdown. But we must remember that ‘public opinion’ is a sometimes invented, or at least embellished, phenomenon, sometimes shaped by polling questions or political expectation. Even more important than that, right now the public has been demobilised. Indeed, there is no ‘public’ to speak of in Covid-hit Britain. We have been utterly atomised, pushed into our homes away from the world. What people say now, in this individuated, concerned state, might be different to what they would say in a properly public forum like a meeting or a hustings or a protest. Being with others influences our opinions and our confidence. The notion of public opinion in a time when public life has been retired is something we should at least be sceptical about.
Against all of this – against scientific advice, media pressure and alleged public opinion – Boris now needs to push back. He needs to think, not about what the papers want to hear or what modellers with no political or economic nous think we should do, but about what is best for the country. This lockdown is proving disastrous. It has ended our freedom, it is causing economic mayhem, it is giving rise to mass unemployment, and it has replaced public life with a culture of atomisation and fear. We need a far more strategic focus on protecting those most vulnerable to Covid-19 alongside a commitment to reopening society and reviving economic life and everyday liberty. Courage will be required. Judgement – and confidence in one’s judgement – will be essential. There will be criticism, there will be op-eds by angry scientists in the press, there will be Twitterstorms about ‘Boris the Butcher’. Ignore it all and lead. And use the institutions of democracy to bring the public along with you. This shouldn’t even be a radical proposal. Indeed, there is already a word for this kind of action: politics.
SOURCE
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