Award-Winning Scientist: Skip the Gloom and Doom and Get Cracking on Solving Climate Change
To glean insights into local weather change, a comparatively small clan of intrepid scientists deploy to a few of the most excessive locations on Earth: the Greenland and Antarctic ice sheets.
From momentary camps, they drill lengthy cores of ice containing chemical clues about historical climates — clues which have revealed key insights into how spaceship Earth’s climatic life help system works.
Like different members of the ice-coring clan, Dorthe Dahl-Jensen, hopes this data can in the end assist inform choices crucial to avoiding the worst potential outcomes of human-caused local weather change.
Saying the world goes beneath is harmful as a result of younger folks will say, ‘Why should I take an education, there is no future for me anyway.’ That has by no means been extra incorrect. Many folks have proven that we are able to resolve this downside.” — Dorthe Dahl-Jensen
Dahl-Jensen is a researcher at the University of Manitoba’s Centre for Earth Observation Science, and a Professor at the Niels Bohr Institute, the University of Copenhagen. She was just lately awarded the Mohn Prize, a prestigious honor for excellence in Arctic analysis.
I sat down to speak with Dahl-Jensen at the current Arctic Frontiers convention in Tromsø, Norway, the place she obtained the award. Joining me was a good friend and fellow science journalist, Tomasz Ulanowski, a reporter for the Polish publication Gazeta Wyborcza. We each posed inquiries to her about what scientists are studying from learning ice. What follows is a mixture of questions and solutions interwoven with background info from my very own reporting.
Make positive to learn via to the finish, the place Dahl-Jensen strikes past the science to handle what she thinks it’s saying about the pressing have to act on local weather change. Unlike what we frequently hear, it’s not truly a miserable and even scary message.
A dome construction is the middle of life at the East Greenland Ice-core Project, or Eastgrip. Members of the ice coring workforce take their meals and calm down inside. Scientists hope the mission will enhance understanding of how ice streams will contribute to future sea-level change, and additionally reveal new particulars about previous weather conditions. (Source: East Greenland Ice-core Project, www.eastgrip.org)
My colleague obtained issues going with this query: What does the ice train us?
She started by noting simply how uncommon water ice is: “Ice is lighter than water,” she said. “There are not many other materials where the solid form is lighter than the liquid form. So it floats on the water.”
That won’t sound so particular, however ice floating on water quite than sinking truly has a profound affect: It helps regulate our planet’s local weather.
The solar units over the Arctic sea ice pack, as noticed in October of 2014. Sea ice helps keep chilly temperatures in the Arctic. (Source: NASA/Alek Petty)
That’s as a result of floating sea ice kinds a shiny protect over the Arctic Ocean and surrounding waters. That protect displays large quantities of photo voltaic power again into house — power that in any other case would heat the area. This helps keep frigid situations in the excessive north.
But human-caused warming has brought on this reflective protect of floating sea ice to shrink at a price of 12.85 p.c per decade since 1979, as measured each September. (This is when the ice reaches its yearly lowest extent at the finish of summer time.) Studies counsel that since the late 20th century, the decline in summer time Arctic sea ice has been steeper than at any time in the previous 1,450 years.
This graph exhibits how the extent of Arctic sea ice has departed from month-to-month means between January 1953 and December 1979. For January 1979 to the current, knowledge have been derived from satellite tv for pc sensors. The report previous to 1979 relies on operational ice charts and different sources. (Image by Walt Meier and Julienne Stroeve, National Snow and Ice Data Center, University of Colorado, Boulder.)
As sea ice shrivels, extra and extra photo voltaic power is being absorbed by the comparatively darkish ocean floor quite than being mirrored again to house. The outcome: The Arctic has warmed twice as a lot as another area on Earth, a phenomenon scientists name “Arctic amplification.”
The proven fact that ice floats on the floor of the sea additionally makes it “super fundamental — because it shields the life in the ocean,” Dahl-Jensen advised us.
At the base of life’s meals internet in Arctic waters are phytoplankton. As winter turns to spring and temperatures naturally heat, sea ice thins, breaks up and and lastly melts, offering phytoplankton with the photo voltaic power they should develop. Springtime blooms of phytoplankton are grazed on by animals often known as zooplankton. Arctic species are comparatively huge and fatty, offering the Arctic cod that feed on them lots of power per chew. The cod are in flip eaten by seals, that are the favourite meal of polar bears.
As the Arctic has warmed, the protect of sea ice has thinned and damaged up earlier, in flip inflicting earlier blooms of phytoplankton. This is sending impacts rippling up the Arctic marine meals internet. For instance, there’s proof that the Arctic zooplankton are being changed by extra southerly, much less nutritious species. And extra southerly fish species appear to be migrating northward.
Thinning sea ice has allowed extra daylight to achieve the water proper beneath the ice, triggering blooms of phytoplankton sooner than in the previous.
Scientists say that a large shift in Arctic marine ecosystems could also be in the offing, however they don’t seem to be but positive what the final result can be. As Dorothy Dankel, a fisheries scientist at Norway’s University of Bergen, put it to me for a function story I wrote not way back, “It’s a fascinating, complex, perfect storm. It can either come out really great, or everything could go down the shithole.”
Shifting to a unique side of Arctic ice throughout our interview with Dahl-Jensen, my colleague requested this: What can it train us about Earth’s historical past?
Dahl-Jensen has lengthy studied the chemical and different clues trapped inside cores of ice drilled from the Greenland ice cap with the intention to acquire insights into previous climates. The hope is that these insights will help us see higher what the future holds as we proceed to pump carbon dioxide and different heat-trapping greenhouse gases into the environment.
Dahl-Jensen famous that yearly’s snowfall on the ice cap “creates a layered record. It is very much like tree rings,” she stated. “You get a layer from each year.” And every annual layer of snow ultimately compresses into ice, trapping climatic clues inside it.
The darkish band on this layered ice core from the West Antarctic Ice Sheet Divide is volcanic ash that settled on the ice sheet about 21,000 years in the past. (Source: Heidi Roop, NSF)
“On the Greenland Ice Sheet we get climate information going 200,000 years back in time,” she stated. “At the bottom, we also find material that is 1 million years old.”
In Antarctica, Dahl-Jensen famous that the layered ice report goes again greater than 800,000 years. “We are hoping for 1.5 million years, and we even believe that it must be at least 5 million years in places,” she stated.
“We use ice as a history book,” she stated. “That’s what fascinates me.”
That historical past ebook comprises details about the make-up of the environment in millennia previous. When snow falls to the floor and is then lined by but extra, it will definitely turns to ice beneath the overlying stress. Air that was trapped between the snowflakes is then preserved, first in bubbles and then inside the matrix of ice crystals. Going again layer-by-layer, and thus year-by-year, scientists can get better that air and decide how a lot carbon dioxide, methane and different gases had been current in the previous.
Tiny bubbles of air are evident on this sliver of Antarctic ice. Air bubbles like this present important details about previous concentrations of greenhouse gases in the Earth’s environment.(Source: CSIRO through Wikimedia Commons)
The icy historical past ebook additionally comprises details about the temperatures that prevailed when the snow first fell. This info is available in the type of chemical fingerprints akin to hotter or cooler situations in the clouds from which the snow fell.
“We can also measure dust particles in the ice, wind-blown dust,” Dahl-Jensen stated. “The dust we find in the Greenland ice cores mainly comes from China. So it moves a long way. And we can measure how much dust is present. This is a function of how dry it was in China, and also a function of how strong the storms were that moved the dust to Greenland.”
In the finish, scientists can measure about “10 different parameters with annual resolution. We use all these 10 parameters to date the core. So we simply count — one year, summer and winter, another year, summer and winter. And we can go thousands of years back in time. This gives just a gold mine of climate information,” Dahle Jensen stated.
“What we see in ice cores, and what is also supported by geological records that go further back, is that every time we’ve had high values of CO2, we’ve had warm temperatures,” she stated. “So there has always been a strong correlation between CO2 and surface temperature. It is surprising that people can doubt whether the high values of greenhouse gases now will result in warmer temperatures once our system adjusts to the vastly changing values.”
Carbon dioxide in the environment has corresponded carefully with temperature over the previous 800,000 years, as seen in these knowledge from the EPICA ice core drilled from Antarctica. Although the temperature modifications had been touched off by variations in Earth’s orbit, the elevated world temperatures launched CO2 into the environment, which in flip warmed the Earth. (Source: NASA Earth Observatory.)
Dahl-Jensen is getting at a facet of local weather change that is not broadly appreciated. Yes, world common temperature has already risen by about 1 diploma C because of emissions of greenhouse gases to this point. But if we had been to close off emissions tomorrow, we might not forestall additional warming fully. Far from it, in reality. We’d nonetheless see way more warming.
That’s as a result of the oceans, which have been absorbing greater than 90 p.c of the warmth that has constructed up, produce lots of inertia in the local weather system. This stems from two bodily info: It takes a very long time for warmth to totally heat the oceans, and additionally a very long time for that warmth to come back out and heat air temperatures.
Source: Rosamund Pearce, Carbon Brief: https://www.carbonbrief.org/heat-absorbed-by-oceans-has-doubled-since-1997)
Here’s how Dahl-Jensen defined it:
“We have a system that is totally out of balance now. The system doesn’t react from day to day. The surface of the sea does, but the ocean as a whole doesn’t. That’s because warming the deep ocean takes place on the scale of a thousand years. So we have a system that takes a thousand years to get into balance. And that means we have a strongly imbalanced system now. As a result we haven’t seen the warming you’d expect from the CO2 we have already put in the atmosphere.”
How a lot extra warming can we count on?
“I would say two degrees,” Dahl-Jensen stated. “But I wouldn’t listen to that if I were you, because there are so many things we do not know.”
Among them: particulars about what occurs to carbon that will get absorbed into the ocean.
“The carbon cycle is probably one of the most difficult balances to make,” Dahl-Jensen stated. “How does the ocean do this uptake?” Thanks to absorption of carbon dioxide into ocean waters, “we see that the ocean is becoming more acid. This reduces its ability to take up more CO2.”
About half of the CO2 that has been pumped into the environment since the daybreak of the industrial period has been absorbed by the oceans via pure processes, making them extra acidic. This harms marine ecosystems, together with coral reefs. (Source: John MacNeill, Climate Central: https://www.climatecentral.org/gallery/graphics/ocean-acidification-process)
In different phrases, the ocean has been doing us a favor by absorbing CO2 that in any other case would have warmed the globe. (But we’ve not been doing the oceans and marine organisms a favor as a result of that CO2 is inflicting acidification — see the graphic above.)
How way more can we rely on the ocean to soak up numerous CO2? Scientists aren’t positive.
I then turned our dialog towards the thought of climatic tipping factors. Many scientists say now we have about 10 years left to keep away from crossing a catastrophic threshold. But how will we reconcile that concept with the proven fact that we could have tons of of years of additional warming in the pipeline it doesn’t matter what we do?
“I don’t really like this,” Dahl-Jenssen stated. “I’m not fond of those dramatic methods of presenting issues . . . I feel the phrase tipping level may be very typically misused, as a result of for my part, tipping level means in the event you reverse the course of you gained’t get again to the similar level once more. I feel if we scale back the CO2 we would truly get again to the similar level once more.”
She additionally says the tipping level argument prevents folks from taking motion. “I think it scares people more than it tells them that we are in a world of opportunities, and [climate change] is something we can solve. We just have to take it seriously and get cracking. We should tell all our young people that this is the most important thing in the world, that we need a super-skilled set of people who can help us solve it in the future. I think that would be a much, much more valuable point of view than telling people that the world will go under in 10 years.”
Young folks, like the Norwegian local weather activist, Greta Thunberg, are already stepping up, Dahl-Jensen noticed. “They are saying, ‘Hey, come on, leave a world for us, we don’t have a Planet B.’ That is simply wonderful,” Dahl-Jensen stated.
“But I think saying the world is going under is dangerous because young people will say, ‘Why should I take an education, there is no future for me anyway.’ That has never been more wrong. Many people have shown that we can solve this problem — we can stop the emissions of greenhouse gases, we can easily go to green energy, and we can also live with a world that becomes warmer.”
Even so, there can be huge challenges, Dahl-Jensen acknowledged. One is that many individuals should migrate from components of the globe that can grow to be not possible to reside in because of sea stage rise, hovering temperatures and different impacts.
“We have to be more tolerant of movement of populations,” she stated. “We can’t allow people to go into war every time some people have to move . . . We have to say, ‘Yes, you’re right, you can’t live there, it’s underwater, or too dry.’ We have to allow for movement.”
Dahl-Jensen identified that water shortages helped ignite the battle in Syria that despatched many refugees streaming into Europe. “Syria was the first climate change war we’ve had,” she stated.
Unless we start to plan for the inevitable will increase in sea stage and extreme warmth and drought which are coming, extra wars fomented by local weather change can be in the offing, she argued.
At the finish of our dialog, Dahle-Jensen mirrored on how troublesome it’s for scientists to assist immediate constructive motion like that.
She associated an incident through which a overseas minister as soon as accused her and different scientists of hampering motion by not offering definitive solutions. “‘How can you expect us to respond when you say something different every day?'” she remembers him saying. In her view, that mirrored a elementary misunderstanding of how science truly works.
“We are not saying something different every day, but we are always upgrading our knowledge,” Dahl-Jensen advised us. “So I answered him again: ‘Why didn’t you expect the monetary disaster? Because , it’s type of an analogous complicated system that folks can’t predict. ‘He got so furious he said, ‘Dorthe, I’ll by no means provide you with a grant once more.’”
It didn’t truly pan out that approach. “He did calm down,” she says.