Submission by the Arctic Methane Emergency Group (AMEG) to the Environment Audit Committee’s Inquiry on Arctic Sustainability - EAC Introduction
The accepted wisdom is that climate change is a direct result of carbon emissions and the greenhouse warming they cause. Thus it is conventionally argued that reducing emissions to zero would halt global warming and climate change. Indeed climate change is often equated with CO2 emissions. But this is a gross oversimplification as it ignores two problems. It ignores the legacy CO2 in the atmosphere which has a lifetime of many decades and will continue warming the planet long after CO2 emissions cease. And it ignores what is happening in the Arctic which we’ll discuss first.
The Arctic is having a huge effect on climate change through a complex interaction between various processes which is important to understand. The rapid warming of the Arctic over the past thirty years has reduced the temperature gradient between Arctic and tropics. This gradient helps to keep the bands of weather systems in place. (There are three bands in the Northern Hemisphere, each with prevailing winds: easterlies in the subtropics; westerlies at mid-latitude; and easterlies in the Arctic and sub-Arctic.) The boundaries between these bands are marked by jet streams, which form patterns called Rossby waves which progress eastwards round the planet. As the gradient is reduced the waves meander more to north and south. They also tend to get stuck. The combination of meandering and stickiness has led to an increase in weather extremes over the past thirty years.
The jet stream tendency to get stuck is made worse by global warming, such as to make the extreme weather longer lasting. Global warming tends also to make extreme droughts and floods more intense by providing increased heat and humidity in the atmosphere. Thus the climate change we have been seeing recently is due to a combination of global warming and even more rapid warming in the Arctic, with the recent El Niño making matters worse.
The legacy CO2 problem means that, to reduce CO2 climate forcing, CO2 has to be removed from the atmosphere faster than it is being added through the burning of fossil fuels. The Arctic problem concerns rapid warming of the region causing melting of snow and sea ice which in turn causes warming in a mutually reinforcing feedback loop or ‘vicious cycle’: as the highly reflective snow and sea ice melt, they expose less reflective land and sea surfaces which absorb extra heat tending to cause further melt. This submission is focussed on the Arctic problem.
The Arctic has long been known as a key component of the Earth System for controlling temperature and climate, which have oscillated dramatically over the past few million years. But for the past few thousand years there has been a balance of albedo (snow and ice reflectivity) between the north and south Polar Regions, which has kept a symmetric arrangement of weather patterns in place, ensuring a constant climate for everywhere on the planet. Ice sheets have remained stable, so that the sea level has also remained constant. However within the last three decades, this balance has been upset by rapid Arctic warming, with potentially dire consequences for the constancy of climate and sea level on which our modern civilisation depends. Rapid Arctic warming was almost certainly triggered by the global warming caused by anthropogenic greenhouse gas emissions (though a reduction in the cooling effect of SO2 emissions may also have had a role).
Recent research on past Earth System behaviour, backed by good observational evidence, suggests that the Arctic is now in the process of switching from a high albedo state, with the Arctic’s ocean covered with sea ice throughout the year, to a low albedo state, with the ocean losing almost all of its ice by the end of each summer and with much reduced snow on land.
Since a completion of this switching process is liable to lock the Arctic into a permanently low albedo state with potentially catastrophic repercussions on climate and sea level, discussed below, everything possible has to be done to prevent completion. The international community must pull together to solve this problem, while there is chance of success. It will involve large-scale interventions, hitherto considered unnecessary and risky by environmentalists, oblivious to the extremely dangerous situation which calls for the most drastic of actions. We urge the committee to regard this situation as representing the true reality for the purpose of this inquiry; even if absolute certainty about the danger has not been established. It is necessary to act on the precautionary principle if there is any doubt about the magnitude about this danger.
The UK can take a lead in promoting the necessary measures and interventions to cool the Arctic and save the sea ice. These interventions will help to reduce the number and/or severity of weather extremes, thereby reducing damage from storms, floods, heatwaves, and droughts in the medium term, or great importance to the UK’s economy. In the longer term, the Arctic albedo should be restored and greenhouse levels brought down to near pre-industrial levels, so that climate is restored to the old norm for everywhere on the planet. This is the ultimate sustainable future for the Arctic, to which all governments must aspire, including our own. The government’s environment policy framework should be redrafted to reflect this.
However there is much positive benefit from an international collaboration to save the sea ice and reduce the level of greenhouse gases in the atmosphere. This is an unprecedented opportunity for countries to work together to restore climate, increase food production and reduce conflict in the world. The UK could take a leading role.