DateJune 23, 2017 | 2:22 pm
Greenland earthquake and tsunami – hazards of melting ice?
Following the news over the weekend with a trip to Greenland this summer at the back of my mind, my attention was immediately caught by reports of a tsunami and earthquake in Greenland. Four people were reported missing. Buildings had been swept away, including the power station on the island of Nuugaatsiaq. Greenland is not the first place that comes to mind in connection with earthquakes and tsunamis. But in fact they are not as rare as you might think.
The cause of the weekend’s event is still unclear. But a tweet from the Greenland Climate Research Centre links to an article in the Washington Post from June 25 2015:
The article reports on a paper published in the journal Science at that time by researchers from Swansea University in the UK, the Lamont-Doherty Earth Observatory at Columbia University and several other institutions. It says the loss of Greenland’s ice can generate “glacial earthquakes”.
“When vast icebergs break off at the end of tidal glaciers, they tumble in the water and jam the glaciers themselves backwards. The result is a seismic event detectable across the Earth”.
Worrying reading indeed, as GCRC wrote in their tweet.
The Washington Post article quoted Meredith Nettles from Columbia, one of the co-authors.
She specifically mentions the tsunami effect:
“The tsunami is caused because the iceberg has to move a lot of water out of the way as it tips over”.
Too early to say
I have been trying to find more information on what the experts think caused this weekend’s particular event. So far, there is no clarity. But the GCRC tweet with link to the Washington Post article seems to indicate they think it could be ice-related.
Another theory is that the quake and tsunami were caused by a landslide. The news agency DPA says the Geological Survey of Denmark and Greenland are still trying to determine the cause of the tsunami.
“Initially, geologists believed it was triggered by an earthquake, but another theory blamed a large landslide from one of the mountains on the fjord system”.
It seems the Danish Arctic Commando published images showing signs of an extensive landslide.
“Tsunamis and large waves at times affect Greenland’s coasts, but, according to the Geological Survey, they are usually caused by landslides and the breaking off of ice from melting glaciers”, the agency writes.
DPA earlier noted that the Danish earthquake authority GEUS had recorded a 4.0 quake.
Warning from Greenland ice cores
One way or other, the weekend tsunami is unlikely to allay anxiety about the effects of rapidly melting substantial quantities of ice.
And a study just published by Germany’s Alfred-Wegener-Institute (AWI) provides more food for thought about human-induced changes to our climate. It indicates that the gradual nature of the changes we are making to the CO2 concentration in the atmosphere is no guarantee that the resulting climate change will also be gradual. On the contrary. Computer models based on information from ice cores from Greenland show that in high latitudes of the northern hemisphere, there were abrupt changes in climate, which the scientists attribute to a gradual increase in CO2.
During the last ice age, they say that the influence of atmospheric CO2 on the North Atlantic Current within a few decades led to an increase in temperature of up to 10 degrees Celsius in Greenland. The study, published in the journal Nature Geoscience, by scientists from AWI and the University of Cardiff shows that in recent earth history, there have been situations when gradual increases in CO2 concentrations at what are known as “tipping points” led to abrupt changes in ocean circulation and climate.
Sudden warm age on the horizon?
Lead author Xu Zhang says the study is the first to prove that a gradual increase in CO2 can set off very rapid warming, based on interactions between ocean currents and the atmosphere.
The authors also show that the rise in CO2 is the main cause of chances in ocean currents during the transition from an ice age to a warm period.
Of course, they add, the framework conditions today are different from those during an ice age, so it is not possible to say the rise in CO2 will have similar effects in future.
But they say they can definitely show that there were abrupt climate changes in Earth’s history, which can be traced back to continual rises in CO2 concentrations.
Reason enough for concern to people living on the coast of Greenland – not to mention the rest of us, given the key role the world’s biggest island, with the biggest freshwater mass in the northern hemisphere sitting on top of it in the form a giant ice sheet, plays in influencing climate and sea levels around the globe?
DateJune 19, 2017 | 3:12 pm
TagsArctic, AWI, Climate, CO2, earthquake, Emissions, glaciers, Greenland, ice, ice age, research, science, Sea level, tsunami
Working for an international broadcaster which has Africa as one of its key target groups, I often find it difficult to interest some of my colleagues in what is happening in the Arctic. So my attention was caught instantly when I came across an article by Chelsea Harvey in the Washington Post: A climate chain reaction: Major Greenland melting could devastate crops in Africa.
DateJune 9, 2017 | 11:17 am
Tags#saveOurOceans, Africa, Arctic, Climate, Greenland, ice, ocean acidification, Renewables, research, science, Sea level, UN talks, Warming
Trump’s alternative reality? No warming, cool oceans, intact coral
“Irene, have you heard the news? Looks like Trump has pulled out of the Paris Agreement.” While the US President kept the suspense up until Thursday night – has he, hasn’t he, will he, won’t he -I struggled to reconcile his action with what I was hearing from a wide spectrum of highly intelligent people with decades of research and experience to their credit.
I was in Kiel this week, on Germany’s Baltic coast, attending a working meeting of the scientists involved in BIOACID, a national German programme (supported by the BMBF, Federal Ministry of Education and Research) to investigate the “Biological Impacts of Ocean Acidification”. It has almost run its course, eight years of research in the bag.
And what I was hearing did nothing to allay my concern about the impacts of our greenhouse gas emissions. We are rapidly and undeniably changing the planet we live on – land and sea. And that applies particularly to the Arctic.
The scientific evidence
Can President Trump really fail to see the dangers of our human interference? Is he really oblivious to what climate change is doing to the ocean that covers 70 percent of the surface of our planet?
Maybe he lives in a parallel universe, where alternative facts prevail.
Back in 2010, I was able to witness the work of some of the scientists assembled in Kiel this week at first hand, as they lowered mesocosms, a kind of giant test tubes, into the Arctic Ocean off the coast of Svalbard. The aim was to find out how the life forms in the water would react to increasing acidification of their environment, as our greenhouse gas emissions result in more and more CO2 being absorbed into the ocean.
Drawing the threads together
Ulf Riebesell is Professor of Professor of Biological Oceanography at, GEOMAR, the Helmholtz Centre for Ocean Research in Kiel, and the coordinator of BIOACID.
When I first met him, he was kitted out in survival gear, supervising the transport and deployment of the mesocosms from Germany up to the Svalbard archipelago. He doesn’t need the cold-weather gear this week, in a summery Kiel, where he gathered representatives of the different working groups involved in the German project to draw some threads together as the project approaches its conclusion in November.
Good timing. The results will be ready to hand to the delegates attending this year’s UN climate extravaganza, COP23, in Bonn. Another key piece in the jigsaw puzzle of how climate change is affecting the world we live in and will determine the future of coming generations.
All creatures great and small
The scientists assembled represent a wide range of expertise. From the tiniest of microbes through algae, corals, fish and the myriad organisms that live in our seas- they have been trying to find out what happens when living conditions change for our fellow planetary residents – and how all this affects an ever-increasing population of humans and the complex societies we live in.
The ocean is changing at an unprecedented rate. It is becoming warmer, even in the depths, and it is becoming more acidic.
The work of Riebesell and his colleagues has shown that in our rapidly warming world, the CO2 that goes into the ocean is reducing the amount of calcium carbonate in the sea water, making life very difficult for sea creatures that use it to form their skeletons or shells. This will affect coral, mussels, snails, sea urchins, starfish as well as fish and other organisms. Some of these species will simply not be able to compete with others in the ocean of the future.
The Arctic predicament
Acidification is not something that affects all regions and species equally. Once again, the Arctic is getting the worst of it. Cold water absorbs CO2 faster. Experiments in the Arctic indicate that the sea water there could become corrosive within a few decades, as Ulf Riebesell has told me on several occasions since I first met him on Svalbard in 2010. “That means the shells and skeletons of some sea creatures would simply dissolve.”
Scientists warn that a combination of acidification, warming and stressors like pollution of all sorts will ultimately affect the food chain. (Indeed that is already happening).
Warming as usual?
While the BIOACID project comes to an end and the scientists fight for new funding to carry on research into ocean acidification, which requires a combination of field-work and modelling, the world continues on course for far more than the two degrees – or 1,5 set out in the Paris Agreement.
“The Paris Agreement is the single best hope for protecting the ocean and its resources”, the magazine reads. But it stresses: “the limits agreed on in Paris will not prevent sea levels from rising and corals from bleaching. Indeed, unless they are drastically strengthened, both problems risk getting much worse. Mankind is increasingly able to see the damage it is doing to the ocean. Whether it can stop it is another question”.
Bending the truth?
At the meeting in Kiel, I asked Professor Hans-Otto Pörtner, the other coordinator of BIOACID, senior scientist at the Alfred Wegener Institute and co-chair of the IPCC Working Group 2 for his view of the current situation, with US President Trump getting set to leave the Paris Agreement:
“Climate change is clearly human made, responsible leadership means that this cannot simply be denied or ignored. I think this is a call for better education and information of the public so that it cannot be misled by bending the truth – and this is what it comes down to. As the last report of the Intergovernmental Panel on Climate Change (IPCC) put it: “Without additional mitigation efforts beyond those in place today, and even with adaptation, warming by the end of the 21st century will lead to very high risk of severe, widespread and irreversible impacts”. In its previous analysis of decision-making to limit climate change and its effects, the IPCC also noted that climate change is a problem of the commons, requiring collective action at the global scale. Effective mitigation will not be achieved if individual agents advance their own interests independently.”
Call to action
Indeed. We are all in this together.
But there is not only bad news:
“It remains to be seen to what extent U.S. emissions will be driven by federal policy, or actions at the State and city level, or by market and technological changes”, Professor Pörtner told me.
There is, it seems to me, an upside to President Trump’s decision to live in his own alternative reality. It galvanizes those of us who live in the real world to make sure climate action goes ahead. China and the EU closed ranks this week. States, companies, civil societies and committed individuals across the USA are stressing they will press on with the green energy revolution regardless.
In the interests of the icy north – and the rest of the planet it influences so considerably – we really have no choice.
DateJune 2, 2017 | 11:37 am
TagsArctic, BIOACID, Climate, CO2, Emissions, Geomar, ocean acidification, Paris Agreement, research, science, Trump, UN talks, Warming