Friday, November 22, 2024
37.0°F

Looking ahead at global temperatures to 2040

by Climatologist Cliff HarrisMeteorologist Randy Mann
| February 6, 2017 12:00 AM

After receiving numerous emails and questions, we finally decided to update our long-term chart and associated article about climate change. Here is Part 1 of the column.

•••

Until late 2006, global temperatures were more than a degree Fahrenheit warmer when compared to the 20th century average. From August of 2007 through February of 2008, the Earth’s mean temperature dropped to near the 20th century average of 57 degrees. Since that time, land and ocean readings have rebounded to the highest levels in recorded history in 2016 with a temperature of 58.69 degrees Fahrenheit.

We, Climatologist Cliff Harris and Meteorologist Randy Mann, believe in rather frequent climate changes in our global weather patterns. Geologic evidence shows our climate has been changing over millions of years. The warming and cooling of global temperatures are likely the result of long-term climatic cycles, solar activity, sea-surface temperature patterns and more. However, mankind’s activities of the burning of fossil fuels, massive deforestations, the replacing of grassy surfaces with asphalt and concrete, the “Urban Heat Island Effect,” are likely creating more harmful pollution. Yes, we believe we should be “going green” whenever and wherever possible.

Our planet seems to be in a cycle of constant change. According to an article by the National Oceanic and Atmospheric Administration (NOAA) on Climate.gov in August 2014, our planet likely experienced its hottest weather millions of years ago. One period, which was probably the warmest, was during the Neoproterozic around 600 to 800 million years ago. Approximately 56 million years ago, our planet was in the Paleocene-Eocene Thermal Maximum as global mean temperatures were estimated as high as 73 degrees Fahrenheit, over 15 degrees above current levels. Ocean sediments and fossils indicate that massive amounts of carbon dioxide were released into the atmosphere.

By contrast, evidence shows there have been at least five major ice ages on Planet Earth. One of the most well-documented and largest, occurred from 850 to 630 million years ago, is called the Cryogenian period. Glacial ice sheets likely reached all the way the equator producing a “Snowball Earth.” Scientists believe that this massive ice age ended due to increased underground volcanic activity and, perhaps, a much warmer solar cycle.

One reason scientists believe that the Earth’s temperature reached a record level in 2016 was the very strong El Nino in the waters of the south-central Pacific Ocean that formed in 2015. El Nino is the abnormal warming of ocean waters that often leads to warmer air temperatures and less snowfall during the winter seasons.

In 2007-08, a moderately strong La Nina, the cooler than normal sea-surface temperature event, combined with extremely low solar activity (storms on the sun), resulted in a period of global cooling and record snowfalls across many parts of the northern U.S., Europe, Asia and the former Soviet Union. The same type of situation, perhaps more severe, could occur again in the early 2020s, especially if we see a strong La Nina combined with very low solar activity.

Climate scientists are not completely certain why ocean waters suddenly warm up and cool down over a period of months or years. The warming of sea-surface temperatures may be due, at least in part, to increased underwater volcanic activity. Researchers are constantly finding new active underwater volcanoes and thermal vents that may be contributing to the warmer temperatures.

Recently, scientists discovered at least three to six times more heat-spewing thermal vents along the seafloors where tectonic plates are pulling apart. In 2003, at least nine hydrothermal vents along the Gakkel Ridge in the Arctic Ocean were found. Arctic ice has been melting at a steady pace in recent years and may be due to the warmer than normal ocean waters. In April 2015, an underwater volcano known as the Axial Seamount, about 300 miles off the coast of Oregon, erupted for a month and added 88 billion gallons of molten rock to the ocean floor.

Since the 1950s, data suggests that ocean temperatures have been getting warmer. According to research at the University of Alabama in 2013, climate models indicate “a natural shift to stronger warm El Nino events in the Pacific Ocean might be responsible for a substantial portion of the global warming recorded during the past 50 years.”

By contrast to the Arctic ice melt, glaciers have been thickening in Antarctica’s eastern interior. That portion of the continent was experiencing increased snowfall and had a gain of about 100 billion tons of ice per year from 1991 to 2008. But, there has been loss of glacier mass in Antarctica’s western region.

Part II of this column will be featured next week. In terms of our local weather, the early portion of February will likely be the snowiest in history. It’s quite possible we will see more significant snowfall between now and early Thursday before the moisture changes over to rain.

We’ve already passed our seasonal snowfall normal of 69.8 inches as Cliff has measured over 81 inches as of early Sunday. Cliff and I wouldn’t be surprised to see our annual total near 90 inches later this week. And, there’s a chance Coeur d’Alene’s final seasonal snowfall will end up over 100 inches for the fourth time in less than 10 years.

Conditions are looking milder beginning late this week as snow is expected to change to rain by Thursday. With rain and warmer temperatures, we will obviously see some snowmelt which may lead to some area flooding. It’s quite possible that high temperatures may be near 50 degrees around Valentine’s Day. Stay tuned.

Contact Randy Mann at randy@longrangeweather.com