Global Warming

What Climate Change is doing to our Lakes

A new study has found that global warming is resulting in rapidly increasing temperatures in lakes worldwide, an alarming find that means freshwater supplies and ecosystems are being threatened by climate change.

The study, conducted by NASA and the National Science Foundation, is the largest study of its kind, using satellite temperature data and long-term ground measurements to examine 235 lakes.

The result were stunning: there was an increase of 0.34 degrees Celsius on average each decade for lakes worldwide, which would have massive effects on drinking water and the habitat for animals and fish.

The 235 lakes the study examined represents half the world’s freshwater supply.

The 0.34 degree increase is greater than the warming rate for both the ocean and the atmosphere. That can mean only one thing: more algal blooms, which can suck up oxygen and water. The study suggests that such blooms will increase 20 percent over the next century, and the kind of blooms that are toxic to wildlife would jump 5 percent.

It would also result in a 4 percent increase in methane emissions. That’s concerning because methane is 25 times more powerful than carbon dioxide.

But rapid changes in temperature like this are more than just bad in terms of creating algal blooms or resulting in methane releases. A quick change in temperature can dramatically alter the survival rate of life forms in a lake, causing some species to suddenly disappear from the Earth. That can upset the balance of an ecosystem, causing further havoc in the wildlife kingdom — which will certainly have ripple effects for mankind.

Arctic air temperature highest since 1900 — Report

The Arctic is heating up, with air temperatures the hottest in 115 years, and the melting ice destroying walrus habitat and forcing some fish northward.

Air temperature anomalies over land were 2.3 degrees Fahrenheit (1.3 degrees Celsius) above average, “the highest since records began in 1900,” said the 2015 Arctic Report Card, an annual peer-reviewed study issued by the National Oceanic and Atmospheric Administration.

Meanwhile, the annual sea ice maximum occurred February 25, about two weeks earlier than average, and was “the lowest extent recorded since records began in 1979.”

“Warming is happening more than twice as fast in the Arctic than anywhere else in the world. We know this is due to climate change, and its impacts are creating major challenges for Arctic communities,” said NOAA chief scientist Rick Spinrad at the annual American Geophysical Union fall meeting in San Francisco.

The average annual air temperature was measured over land between October 2014 and September 2015. It marked a 5.4 degree F (3 degree C) increase since the beginning of the 20th century.

The minimum sea ice extent, measured on September 11, 2015, was the fourth lowest in the satellite record since 1979. “Arctic minimum sea ice extent has been declining at a rate of 13.4 percent per decade” relative to the 1981-2010 average, said the findings.

In the 1980s, older, thicker ice made up about half of the ice sheet, but now, what is known as “first year ice” dominates the winter ice cover and made up 70 percent of the March 2015 ice pack. This thinner, younger ice is more likely to melt in the summer than thicker ice, said the report.

Snow cover across the Arctic has also been declining and is down 18 percent per decade since 1979.

This year, Greenland experienced its first significant melting event since 2012, and lost more than half of its surface area.

Global Warming

Arctic Sea Ice Annual Minimum

Arctic sea ice hit its annual minimum extent for the summer on Sept. 11, 2015. The ice covered 1.7 million square miles (4.41 million square kilometers), seen here superimposed on the 1981-2010 average, drawn as a gold line. 2015 represents the fourth lowest since satellite observations began.

Environment

Acidic Arctic Threatening Marine Life

Global greenhouse gas emissions have caused the level of acidity in the Arctic Ocean to rise 30 percent since the dawn of the Industrial Age, threatening to bring dire consequences to the region’s fragile ecosystem.

Delegates to the Arctic Monitoring and Assessment Program conference in Bergen, Norway, were told that the pollution has caused pH levels to reach their lowest levels in the Arctic for at least the last 55 million years.

The Arctic is most vulnerable to acidification because its cold waters can absorb more carbon dioxide.

Its extensive freshwater inflow also makes it less able to chemically neutralize the acidification effects of the greenhouse gas.

It would take tens of thousands of years for the Arctic Ocean to return to the acidity levels that prevailed before the mid-1800s even if all CO2 emissions were halted today, scientists say.

The current acid levels threaten some species with a direct risk of extinction, and fish stocks may also be affected.

Environment

Arctic sea ice is shrinking at a rate much faster than scientists ever predicted and its collapse, due to global warming, may well cause extreme weather this winter in North America and Europe.Decades ago, Arctic ice covered about 6 million square miles of sea in the winter, and would shrink to about 3 million square miles in the summer. The rate of summer melt increased enormously around 2005, however, and today scientists say Arctic ice covers only about 1 million square miles.

The loss of Arctic ice has several effects. Ice reflects heat and solar energy back into space. With less ice cover, that heat energy is instead absorbed by the ocean, which warms and melts more ice. Currently, the Arctic region is the fastest-warming region on the planet, and the change in temperature will probably influence weather patterns here and in Europe.

The heating and cooling of Arctic seawater has been affecting the jet stream – the river of air that flows from west to east high above the Earth’s surface – and has slowed it down, Francis said. The jet stream controls the formation and movement of storm systems, so when its movement slows, weather conditions persist for longer periods of time over the same area. They get “stuck.”