The Arctic Ocean continues to warm up
Ocean temperatures continue to warm up across the globe. Scientists and forecasters in Australia and at the National Oceanic and Atmospheric Administration are calling for the formation of a new El Nino, the abnormal warming of sea-surface temperatures, before we see the end to 2018.
As I’ve mentioned earlier, when our region experiences an El Nino, snowfall totals in the Northwest are often below normal levels. Cliff and I will issue our snowfall forecast next week.
Ocean waters have been climbing along the equatorial regions of the south-central Pacific Ocean. But, sea-surface temperatures have been consistently warmer in the Arctic regions since 1990, as much as 5-10 degrees Fahrenheit above normal levels in recent years.
Recent data from NOAA shows that the sea ice cover is relatively young, with older and thicker ice accounting for only 21 percent of the ice cover in 2017. Back in 1986, the thicker ice was 45 percent of total ice cover.
According to a study in Nature Communications, when the Arctic regions turn warmer, during the mid to late winter when the Arctic warming trend is greater than usual, cold and heavy snows are often more frequent in the midwestern and eastern U.S. as well as parts of Europe and Asia. In 2018, the eastern U.S. had record-breaking freezing temperatures, a “bomb cyclone,” and an all-time record three nor’easters in just 11 days.
Some scientists believe that the warmer Arctic regions may show a correlation with a weakening of the polar vortex, an area of very cold air that circles the North Pole. When the polar vortex weakens, the colder air will move southward. That brings frigid conditions down into the U.S., especially east of the Rockies as well as Europe and Asia.
The warmer ocean waters in the Arctic could also be impacting the polar jet stream, the river of air that often directs Pacific storms into the western U.S. One theory points to the possibility that we’re seeing longer periods with a high pressure system over the western U.S. as the upper-level jet stream winds are becoming weaker. Therefore, weather patterns are taking longer to develop or move, which will lead to more extreme conditions such as drought, heat, cold and floods.
For the second year in a row, Coeur d’Alene and the rest of the western portions of the country experienced one of the warmest and driest summer seasons in history. As a result, 2018 was another bad wildfire season as about 8.1 million acres have burned. As of late last week, there were over 35 large fires including 10 in Washington, 8 in Montana and 5 in Idaho.
Based on the 20th century average of 57 degrees Fahrenheit, the Earth’s temperature is currently almost 2 degrees Fahrenheit above that figure. Some stations in the Arctic regions, such as Barrow, Alaska, were reporting mean temperatures of close to 10 degrees above normal since 1980. However, this region did have one of the coldest Augusts since 2006.
Long-term climate records do indicate that the Arctic region can experience climate changes very quickly. When the last ice age ended about 15,000 years ago, air temperatures increased by nearly 30 degrees in Greenland over several decades. And, so far this year, Greenland has experienced about three times more hours above the freezing mark.
The burning of fossil fuels and other factors relating to climate change are some of the main reasons that climate scientists point to the warming Arctic. Earlier this month, a new report from the Intergovernmental Panel on Climate Change that our planet’s temperature will likely rise about a half-degree Celsius between 2030 and 2052 that would lead to bigger weather extremes and catastrophic impacts of global warming.
It’s also possible that underwater volcanic eruptions are causing the big rise of ocean temperatures in the Arctic regions. Beneath the Arctic Ocean stretching about 1,100 miles from the northern tip of Greenland to Siberia is the Gakkel ridge, a giant chain of volcanoes. Some areas of this ridge are 3.4 miles deep with its summits rising 3.1 miles above the seafloor. Based on this information, the Gakkel ridge is bigger than the Alps.
In recent years, there is evidence to suggest there have been extensive swarms of earthquakes, methane releases and volcanic eruptions. Back in 2010, there was the large volcanic eruption in Iceland which lies just outside of the Arctic Circle. It’s quite possible that there has been an increase in underwater volcanic activity. In Antarctica, there were 91 volcanoes discovered last year. So, as usual, only time will tell.
In terms of our local weather, despite the recent valley rain showers and mountain snow showers from a “backdoor” storm system late last week, conditions are still drier than normal. A strong high pressure system is expected to dominate our weather, bringing us sunny days and cold nights into at least next week.
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Contact Randy Mann at randy@longrangeweather.com.