At the Poles
The Arctic is changing incredibly rapidly; much more rapidly than the rest of the world. ~ American climatologist Tim Garrett in 2018
The polar regions are especially prone to global warming. Due to geothermal feedback loops, the Arctic has been hotting up at twice the rate of the global average over the past century. In early 2019, Arctic air temperatures were 40 °C above the 20th-century historical average.
What happens in the Arctic doesn’t stay in the Arctic: it affects the rest of the planet. The Arctic has huge influence on the world at large. ~ American oceanographer Timothy Gallaudet
By upsetting the energy balance of the planet we are changing the temperature gradient between the equator and the pole. This in turn sets in motion major reorganisations of the flow patterns of the atmosphere and ocean. ~ English climatologist Chris Rapley
Besides heat, the Artic has been especially hard hit by ocean acidification.
The Arctic Ocean is the first ocean where we see such a rapid and large-scale increase in acidification, at least twice as fast as that observed in the Pacific or Atlantic oceans. ~ Chinese marine chemist Wei-Jun Cai in 2017
Changes in the Arctic atmosphere affect the lower latitudes via the polar vortex and jet streams. The polar vortex is the gyre of low pressure and cold air at both of the planet’s poles.
A jet stream is an atmospheric river that nominally flows from west to east in accordance with Earth’s rotation, and with wavy latitudinal shifts according to climatic conditions. There are polar (~50º–60º latitude) and subtropical (30º) jet streams.
As the Arctic warms, the polar vortex weakens and the polar jet stream becomes wavier, bringing warmth to the Arctic and cold air to lower latitudes.
The Arctic is undergoing dramatic changes linked to climate change, including a rapid decline in sea ice. As sea ice shrinks, it disrupts the natural functioning of the ecosystem. ~ American marine biologist Amber Hardison
At the current rate of warming, the Arctic will ice-free by 2045; probably sooner. The Arctic Ocean has not been iceless in the summer for over 125,000 years.
Polar bears are headed to extinction, as are penguins and many other animals dependent upon a habitat with sea ice.
No sea ice means no seals. And no seals means no polar bears. ~ Canadian zoologist Andrew Derocher
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Changes at the south pole are also occurring, but at a more glacial pace. Southern Ocean currents which surround Antarctica are helping keep the continent cool, as upwelling deep, cold water fends off warming.
The oceans are acting to enhance warming in the Arctic while damping warming around Antarctica. ~ American oceanographer Kyle Armour
The cool at the south pole won’t last. Already sea ice shelves are cleaving around Antarctica and floating out into the ocean. The melt rate of Antarctica’s ice sheet tripled in the decade of 2008–2017. Antarctic ice loss in 2018 was 5 times faster than 20 years earlier.
When the ice finally starts seriously melting at the south pole, it is likely to trigger catastrophic changes. There are 138 sleeping volcanoes underneath Antarctica, some of which are likely to wake up when the ice cover lessens. Then the south pole will become a blow torch to global warming.
Without ice sheets on top of them, there is a release of pressure on the regions’ volcanoes and they become more active. ~ English geophysicist Robert Bingham