In December, new reports from a significant Earth science conference and the annual Arctic report card from the National Oceanic and Atmospheric Administration (NOAA) showed that extreme warming of the Arctic and Antarctica is underway. Many never-before-seen things are happening. Below are some significant aspects of this news as reported from DTNPF, The Washington Post, and Alberta Farm Express.
DTN’s Senior Ag Meteorologist Bryce Anderson, calls NOAA’s announcement surprising. Temperatures in the Arctic are rising at twice the speed of anywhere else on Earth. Sustained warming of the Arctic atmosphere and ocean are causing changes in the environment in ways that have been predicted, and in ways that are unexpected.
Loss of Sea Ice
We know the warmer temperature are going to cause the ice to melt- but how much? In the Bering Sea during 2017 and 2018, winter sea ice was at a record low. It’s estimated that it lost an area of ice the size of the state of Idaho. Overall, scientists believe the Arctic is a period of transition. Old ice- ice that has been there for multiple seasons- is melting and being replaced with thinner ice, or just disappearing altogether. In 1985, one-sixth of Arctic ice was multi-year ice. Now, the multi-year ice is estimated to make up one-hundredth of total amount of Arctic ice.
If Arctic ice continues to thin, many scientists argue that it will give global warming an added boost. Chris Mooney of The Washington Post say the oldest sea ice can be thought of as a “glue” that holds the Arctic area together. Its presence has helped the area remain cold throughout the summer months. More of the Arctic is now younger and thinner ice, which melts more easily than the older ice. The ice is losing overall volume, which is a more significant measurement than area.
Now, ice-free Arctic summers are looking more and more likely. If that happens, the planet will warm at an even faster rate.
There is a well-known feedback loop in the Arctic, caused by the reflectivity of ice and the darkness of the ocean. When the Arctic Ocean is covered by lighter, white ice, it reflects more sunlight back to space. But when there is less ice, more heat gets absorbed by the darker ocean — warming the planet further. That warmer ocean then inhibits the growth of future ice, which is why the process feeds upon itself.
Open ocean water absorbs twice as much sunlight as floating sea ice, and ice loss has already contributed to the warming of the planet as a whole.
Antarctica is losing ice too. NASA’s Icesat 2 satellite shows that the ice there is thinning. The Dotson ice shelf has lost more than 390 feet in thickness since 2003. In addition, four glaciers at Vincennes Bay have lost 9 feet of ice thickness since 2008. This is significant because Antarctic melting is more strongly associated with sea level rise.
The loss of winter sea ice impacts wildlife. Winter-nesting birds are building fewer nests. The black guillemot for example, had only 85 nesting pairs this season on Cooper Island. In past years they’ve had more than 200 nesting pairs. There’s been a 55% drop in herd size of caribou and wild reindeer because warmer temperatures leave the herds susceptible to fly and parasite infestations over a greater portion of the year. More algal toxins are able to move in with the warmer temperatures and are hurting many birds, mammals, and shellfish.
Brenda Schoepp of Alberta Farm Express says that changes in the Arctic like the reduction of polar ice, melting of permafrost, and less snow will all affect Canadian agriculture. Many areas of Canada that have historically been a block of ice are now opening up in parts of the Northwest Territories, Yukon, northern Peace, and northern Ontario. Farming is now possible in many places it wasn’t before because of the loss of ice, warmer temperatures, and long summer days.
Some farm groups argue that this is a good thing. Food security in the northernmost regions of Canada has long been an issue, and greater ability to farm the lands there could be a solution to this problem. But Schoepp argues that it’s not quite that simple.
Rising temperatures impact the permafrost. The permafrost is it’s own ecosystem, and many scientists are concerned that as it thaws, large amounts of carbon will be released. Carbon contributes to the warming of the Earth’s atmosphere, which impacts freezing and snow- and 80 percent of Canada’s freshwater supply is derived from Arctic and Subarctic snow. Less snow means less fresh water, and could make farming in these areas unsustainable.
In addition, as temperatures rise, sea levels will rise. Canada’s richest farmland near warm water deltas will become “salinity wastelands,” and unusable for farming.
I can’t support the train of thought that believes climate change and the consequential melting of ice and permafrost in opening up northern farms is going to be the solution for food insecurity issues for Canada, particularly if there remains a shortage of fresh water.
Though warmer weather in the Arctic might open up new areas to food production, the overall effects of global warming and its impact on fresh water supplies in Canada might make that challenging. NOAA scientists report that the dynamics of the sea ice in the poles is changing- more of the old ice is melting- which is resulting in a lower volume of ice. Newer ice is less robust. It breaks and melts more easily, leaving open the possibility of an ice-free Arctic in our near future. If that happens, scientists predict global warming to ramp up at an even steeper rate. The data is there- the climate is changing, the poles are melting. The question remains: What can we do to stop it?