Mankind is pumping so much carbon dioxide into the atmosphere that it could postpone the next ice age by more than 100,000 years, according to new research which finds humans are having a “mind-boggling” impact on the Earth.
The volume of CO2 emissions that has accumulated in the atmosphere is so great that it has fundamentally changed the relationship between people and the planet as human behaviour radically alters the way the system operates, the research shows.
The study found that the next ice age would be pushed back by about 50,000 years even if emissions stopped overnight. And if the volume of greenhouse gases forecast to be produced in the coming decades comes to pass it could be postponed by more than 100,000 years.
The impact of greenhouse gases is so profound and long-lasting because they can linger in the atmosphere for centuries. During this time they upset the evolution of the ice sheets of the Northern Hemisphere which build up gradually over a period of 90,000 years through a complex, highly uneven, feedback mechanism of cooling temperatures, increasing snowfall, rising levels of reflected sunlight and falling temperatures.
“It is mind-boggling that humankind is able to interfere with a mechanism that shaped the world as we know it,” said Dr Andrey Ganopolski, lead author of the study, by the Potsdam Institute for Climate Impact Research.
“But our study shows that CO2-emissions from burning oil, coal and gas are already sufficient to postpone the next ice age for another 50,000 years,” Dr Ganopolski added.
And unless drastic action is taken to swiftly cut emissions the next ice age could be pushed back considerably further than that, according to Dr Ricarda Winkelmann, co-author of the research, published in the journal Nature.
“Due to the extremely long life-time of CO2 in the atmosphere, past and future emissions have a significant impact on timing of the next glacial inception,” she said.
“Our analysis shows that even small additional carbon emissions will most likely affect the evolution of the Northern Hemisphere ice sheets over tens of thousands of years and moderate future CO-emissions are bound to postpone the next ice age by at least 100,000 years,” said Dr Winkelmann.
Climate change around the world - in pictures
Climate change around the world - in pictures
Calved icebergs from the nearby Twin Glaciers are seen floating on the water in Qaqortoq, Greenland
2/17 Coastal systems and low-lying areas
Flood damaged streets in Queens, New York where the historic boardwalk was washed away due to Hurricane Sandy in 2012. The report predicts that by the end of the century “hundreds of millions of people will be affected by coastal flooding and displaced due to land loss”
3/17 Food security
Widespread drought devastated a corn crop on a farm near Bruceville, Indiana in 2012. The report forecasts that climate change will reduce median yields by up to 2 per cent per decade for the rest of the century
4/17 The global economy
The Evening Standard headline board showing the words 'Black Friday Shares Crash' in London in October 2008 in London. The report warns a global mean temperature increase of 2.5C above pre-industrial levels may lead to global aggregate economic losses of between 0.2 and 2.0 per cent
5/17 Human health
A child suffering from malnutrition and diarrhoea is seen at the Banadir hospital in the Somalian capital of Mogadishu in 2009. Climate change will lead to increases in ill-health in many regions, with examples including an increased likelihood of under-nutrition.
6/17 Human security
A Muslim migrant holds his son as they are detained at the Immigration Police Office on the Thai-Malaysian border in March 2014. The report states that climate change over the 21st century will have a significant impact on forms of migration that compromise human security
7/17 Freshwater resources
A villager walks through a parched paddy in Tianlin county, China in 2012. The report finds that climate change will “reduce renewable surface water and groundwater resources significantly in most dry subtropical regions"
8/17 Unique landscapes
Machair, a grassy coastal habitat found only in north-west Scotland and the west coast of Ireland, is one of the several elements of the UK’s “cultural heritage” that is at risk from climate change
A boat navigates among calved icebergs from the nearby Twin Glaciers in Qaqortoq, Greenland. Boats are a crucial mode of transportation in the country that has few roads. As cities like Miami, New York and other vulnerable spots around the world strategize about how to respond to climate change, many Greenlanders simply do what theyve always done: adapt. 'Were used to change, said Greenlander Pilu Neilsen. 'We learn to adapt to whatever comes. If all the glaciers melt, well just get more land
The Svalbard Global Seed Vault is seen after being inaugurated in Longyearbyen, Norway. The 'doomsday' seed vault built to protect millions of food crops from climate change, wars and natural disasters opened deep within an Arctic mountain in the remote Norwegian archipelago of Svalbard
A technician preparing to drain a vast underground lake at the Tete Rousse glacier on the Mont Blanc Alpine mountain, to avert a potentially disatrous flood. Some 65,000 cubic metres (2.3 million cubic feet) of water have gathered in a cavity, dangerously raising the pressure beneath the mountain, a favourite spot for holiday makers in Saint-Gervais-les-Bains
Oroumieh, one of the biggest saltwater lakes on Earth, has shrunk more than 80 percent to 1,000 square kilometers in the past decade. It shrinks mainly because of climate change, expanded irrigation for surrounding farms and the damming of rivers that feed the body of water
Cracked mud is picture at sunrise in the dried shores of Lake Gruyere affected by continous drought near the western Switzerland village of Avry-devant-Pont. A leading climate scientist warned that Europe should take action over increasing drought and floods, stressing that some climate change trends were clear despite variations in predictions
Cattle graze on grassland that remains dry and brown at the height of the rainy season in south of Bakersfield, California. Its third straight year of unprecedented drought, California is experiencing its driest year on record, dating back 119 years, and dating back as far as 500 years, according to some scientists who study tree rings
An aerial view shows tents of flood-displaced people surrounded by water in southern Sehwan town. United Nations Framework Convention on Climate Change (UNFCCC) executive secretary Christiana Figueres met with people displaced by last year's devastating floods. Catastrophic monsoon rains that swept through the country in 2010 and affected some 20 million people, destroyed 1.7 million homes and damaged 5.4 million acres of arable land
An aerial view of flooding in North Wagga Wagga. Climate change is amplifying risks from drought, floods, storm and rising seas, threatening all countries but small island states, poor nations and arid regions in particular, UN experts warned
Damages caused by a landslide on the Pan-American highway near La Moramulca, 55 Km south of Tegucigalpa. International highways have been washed out, villages isolated and thousands of families have lost homes and crops in a region that the United Nations has classified as one of the most affected by climate change
The paper defines moderate human emissions as being a cumulative amount of between 1000 billion and 1,500 billion tonnes.
Mankind has already emitted more than 500 billion tonnes of CO2 into the atmosphere and many scientists fear fossil fuels are so entrenched in the energy system that emissions could eventually total well over 1,000 tonnes before their expected eradication at some point during the second half of this century, even after world leaders recently agreed a deal in Paris last month to step up action against climate change.
The research is the first to quantify the impact of manmade CO2 emissions on the timing of the next ice age and demonstrates just how much the relationship has changed between humanity and the planet, the authors said.
“Like no other force on the planet, ice ages have shaped the global environment and thereby determined the development of human civilisation,” said Dr Winkelmann.
“We owe our fertile soil to the last ice age that also carved out today’s landscapes, leaving glaciers and rivers behind, forming fjords, moraines and lakes. However, today it is humankind with its emissions from burning fossil fuels that determines the future development of the planet,” she added.
How do ice ages occur and why do they keep happening
Ice ages occur about every 20,000 years with a major one happening every 100,000 years.
They are triggered by predictable changes to the earth’s orbit around the sun, which periodically take the planet further from the sun, meaning that it cools down.
By itself, this wouldn’t be nearly enough to inflict an ice age. But the change sets in motion a lengthy feedback mechanism in which – very unevenly and over tens of thousands of years – the distancing of the world from the sun causes temperatures to drop, increasing the amount of snowfall and ensuring more sunlight is reflected back into the atmosphere. This, in turn, further reduces the temperature and the process begins again.
But with CO2 levels at their current level, any cooling set in motion by changes in the orbit are outweighed by the warming effect – making an ice age impossible and upsetting the evolution of the Northern Hemisphere.