Between 115 000 and 11 700 years ago, the Earth would have been almost unrecognisable. Massive ice sheets covered Northern Europe and Northern Asia, and about half of North America, and global sea levels were as much as 130m lower than today.
In this period, known as the Last Glacial Period, the climate was much cooler and drier than today. It was punctuated by some of the largest and most rapid climate change events in Earth’s recent geological history.
For a long time, scientists have pondered how closely timed these abrupt climate change events were between Greenland and other regions of the world, far beyond the Arctic.
In our research, published in August in the journal Science, we show that abrupt climate changes across the Northern Hemisphere and into the southern mid-latitudes occurred simultaneously, within decades of each other, throughout the Last Glacial Period. We also determined exactly when the abrupt changes occurred much more precisely than before.
This can help us predict how abrupt climate changes might play out in the future.
A SERIES OF ABRUPT CHANGES
Scientists can peer into Earth’s climate history through long ice cylinders, called ice cores, drilled from the Greenland ice sheet. Changes in the chemical composition of these ice cores reveal that the surrounding atmospheric temperature repeatedly warmed by 8°C to 16°C, and each time within just a few decades. Each warming event was followed by a more gradual period of cooling. These abrupt warming and cooling events happened more than 25 times throughout the Last Glacial Period, and are known as Dansgaard-Oeschger events. They reflect changes in circulation patterns of the Atlantic Ocean.
ãã®èšäºã¯ Farmer's Weekly ã® September 18, 2020 çã«æ²èŒãããŠããŸãã
7 æ¥éã® Magzter GOLD ç¡æãã©ã€ã¢ã«ãéå§ããŠãäœåãã®å³éžããããã¬ãã¢ã ã¹ããŒãªãŒã8,500 以äžã®éèªãæ°èã«ã¢ã¯ã»ã¹ããŠãã ããã
ãã§ã«è³Œèªè ã§ã ?  ãµã€ã³ã€ã³
ãã®èšäºã¯ Farmer's Weekly ã® September 18, 2020 çã«æ²èŒãããŠããŸãã
7 æ¥éã® Magzter GOLD ç¡æãã©ã€ã¢ã«ãéå§ããŠãäœåãã®å³éžããããã¬ãã¢ã ã¹ããŒãªãŒã8,500 以äžã®éèªãæ°èã«ã¢ã¯ã»ã¹ããŠãã ããã
ãã§ã«è³Œèªè ã§ã? ãµã€ã³ã€ã³
Meet some of the heroes behind avitourism destinations
Exploring what the Garden Route offers birdwatchers, Brian Berkman discovers some special people who run hospitable places to meet and see a variety of species.
What the Citrus Academy offers aspiring producers
Cobus du Plessis takes a look at the Citrus Growers' Association of Southern Africa's Citrus Academy and how it is helping to develop aspiring farmers in the sector.
Seeder kick-starts vegetation in challenging environments.
Dr George Craven of Noorspoort, Steytlerville, in the south-eastern Karoo, is successfully using a home-built 'bedstead seeder' to re-establish veld plants in an arid area, writes Roelof Bezuidenhout.
Sowing seeds for the future: unravelling estate planning challenges for farmers
PJ Veldhuizen, managing director of specialist commercial law firm Gillan & Veldhuizen Inc, emphasises the critical role of legal expertise in unravelling the ins and outs of estate planning.
Visiting olive oil producers in Spain
A group of agricultural journalists representing 15 member countries of the International Federation of Agricultural Journalists recently visited the south of Spain to explore the agricultural operations and opportunities unique to that region. Magda du Toit reports.
SA genetics ready to take on the world
The South African Braunvieh has all it takes to become a serious contender in the international red meat production arena, says Gawie Naudé, owner of the award-winning Eduan Braunvieh Stud near Rhodes in the Eastern Cape. Annelie Coleman reports.
Local company serves farmers and communities
Magda du Toit writes about how a company in Limpopo is training and empowering agricultural workers.
Except for pork, meat prices traded lower this past month
While the local livestock industry continues to battle many challenges, an uptick in beef exports as well as the poultry industry's strides to replenish the chicken supply bode well, says Absa AgriBusiness.
Africa goes from net carbon sink to source
New research shows Africa's impact on greenhouse gases and the need to focus on climate-smart agriculture, writes Jyothi Laldas.
Zero-residue fresh produce a reality
Retail giants are calling for caution when using biologicals and chemical pesticides, writes Lindi Botha.