- Around 50 million years ago, the Arctic region was a warm temperate forest rather than today's frozen landscape. This was due to much higher CO2 levels during a period known as the Eocene hothouse. - A tiny aquatic fern called Azolla that grew in the Arctic's freshwater lakes and rivers is theorized to have caused global cooling. Azolla absorbed large amounts of CO2 from the atmosphere, eventually storing it in peat deposits on the lake and sea floors. - Within 800,000 years of the "Azolla Event", CO2 levels dropped by over 75%, Antarctic ice sheets formed, and global temperatures declined, marking the transition to today's cooler "Icehouse Earth" climate

1. The Azolla EventThe Creation of the Modern Earth’s ClimateBy Jeff TaylorOlympus High SchoolGet You High School Diploma Online!

2. Today’s Rocks Explain The Past’s Climate

3. Did you know that the Arctic Circle was a warm swamp 50 million years ago?ThenNow

4. Ellesmere Island TodayOne of the northernmost pieces of land on EarthVery cold, very dry, very dark in winterWinters average high -30° C (-22° F)Summers average high 6°C (43° F)This is summer where you are lucky if it gets above freezing

5. Ellesmere Island50 million years ago

6. South CarolinaToday

7. Fossils of Ellesmere IslandOn this cold arctic island are preserved stumps and fossils of an ancient temperate forest, which had a climate similar to South Carolina today!http://thecanadianencyclopedia.com/index.cfm?PgNm=TCE&Params=A1ARTA0010389

8. But, How Could That Be?Today50 Million Years Ago

9. The Position is SimilarSometimes different climates can be explained by movement of continents due to plate tectonics. But, in this case, Ellesmere Island is pretty close to where it was 50 million years ago.North PoleLomonosov ridge

10. So, What’s The Deal?

11. Hothouse EarthFor over 200 million years, up to and past the extinction of the dinosaurs, the Earth was much warmer than it is today.How much warmer? About 8-10° F worldwide average temperature.That was enough to have forests in Antarctica and tropical jungles in Seattle. Carbon Dioxide levels were some 6 times higher than today.

12. The EoceneAbout 50 Million Years AgoDinosaurs had been extinct for 15 million yearsMammals were becoming the dominant animal on EarthIt was tropical all the way north to the Pacific NorthwestIt was temperate all the way to the polesNo ice caps at either poles and no glaciers

13. Evolution of the WhaleEocene Brought About Remarkable Mammalian Evolution

14. Some Differences Between Now and Then With no ice caps, the sea levels were much higher, flooding lower areas

15. Antarctica was covered in forests and there were no glaciers

16. India has not yet hit Asia, so the Himalayas could not block moisture.

17. South America and North America were not connected, so ocean currents could go right between them and animals could not cross back and forth.

18. Europe and Africa had not collided, so there were no Alps yet.But, why so warm?That isn’t completely understood yet. But, here are some theories and evidence. CO2 levels were way higher than today (about 6 times). This greenhouse gas captured more solar energy.

19. Ocean currents could transport heat better due to the configuration of the continents.

20. No ice caps meant no white snow to reflect sunlight back into space.So, why did it get cold?Around 47 million years ago, the “Hothouse Earth” ended and within 800,000 years the temperature dropped dramatically.By 45 million years ago, the temperature began to approach the current conditions. CO2 dropped dramatically

21. Ice caps formed over Antarctica

22. “Icehouse Earth Phase” has begun“Icehouse Earth”What Could Cause Such a Dramatic Change?It is currently theorized that a fern caused a dramatic change in Earth’s climate that has continued for the last 47 million years.Wait a minute….A FERN?

23. Meet AzollaThis is a tiny little aquatic fern found in swamps and bogs today

24. Azolla Ecology Grows in tropical and subtropical regions

25. Is intolerant to freezing conditions

26. Can be a pest that will completely cover waterwaysAzolla – The “Super Plant”Azolla has the amazing ability to double its biomass in just 2-3 days.