Climate Wire | Calm and tropical Hawaii seems like the last place on earth to see snow and ice. However, the tips of some of the highest mountains in the archipelago often drop below freezing in winter and are covered in a magical blanket of snow.
That’s not all. Another surprise lies near the summit of Mauna Kea, Hawaii’s highest peak, at nearly 14,000 feet. Two patches of rare tropical permafrost. This is the type of continuously frozen soil most commonly associated with the frigid Arctic.
Mauna Kea is the only known occurrence in Hawaii, but it is probably extinct. Research has shown that patches have shrunk over time.
Norbert Schölhofer, a researcher at the nonprofit Institute for Planetary Science, said they could disappear within decades at the rate the planet is warming. He has been studying Hawaiian permafrost for many years.
“It’s getting warmer and warmer,” he said. “So there is no way permafrost can survive.”
Schorghofer’s research is primarily focused on other planets such as Mars. He became interested in Hawaii’s unusual permafrost. The reason is that its permafrost can resemble exotic landscapes. Very cold and bare regions of the Earth can sometimes help scientists understand what they are like on other planets.
However, his motivations have changed over the years.
“After years of research, we know that this is nothing like Martian ice,” he says. It’s too humid in the mountains because of the amount of snow that melts each season.
Instead, “I think what I did was actually an environmental project rather than a global project,” he said.
Hawaii’s permafrost was first scientifically documented in 1969 by researcher Alfred Woodcock. At the time, he theorized it could date back to the Pleistocene, which he ended more than 10,000 years ago. But Schorghofer says it’s “pure speculation.”
“It could be younger, or it could have been formed more recently,” he says. Perhaps sometime during the so-called Little Ice Age, a period of regional cooling that ended in the mid-19th century.
All scientists can say with certainty is that the region must have formed when it was much colder than it is today.
Several factors have allowed it to persist over the years. A patch of permafrost sits within the cradle of He Two Craters near the summit of Mauna Kea and helps provide shade from the sun. When it snows, it also reflects the sun.
Surface temperatures still tend to exceed a few degrees below freezing. However, complex processes such as the placement of snow and ice, and the way water melts and penetrates the top layers of the soil, transferring heat between the ground and the atmosphere, make the soil cooler below ground than at the surface. tend to. surface.
Permafrost does not only exist in the tropics. Kenji Yoshikawa, a researcher at the University of Alaska Fairbanks who has worked with Schorghofer for many years on permafrost, says there are spots in the Andes of Mexico and Peru, as well as Mount Kilimanjaro in Tanzania. He has traveled all over the world documenting sites of this kind.
But because it’s so close to the equator, permafrost is usually only found at altitudes above 17,000 feet, Yoshikawa added. Hawaii is doubly rare because permafrost exists just above 13,000 feet.
Now, the warming climate is catching up. Back in 1969, Woodcock observed that the area was already in danger of thawing, Schorhofer said.
Of the two patches currently known to exist, Woodcock detailed one when he first spotted it. At the time it was at least 80 feet in diameter and about 30 feet deep.
Schorghofer and his colleagues conducted a geophysical survey in 2016 to see how the site has changed over the years. They found it to be smaller and shallower, a fact reported in 2017 and re-emphasized in another paper this year.
“It’s shrinking on all fronts,” Schorhofer said.
Yoshikawa suggested that recent changes in Earth’s El Niño-La Niña cycle, a natural climate cycle that causes periodic changes in the temperature of the Pacific Ocean, may be contributing to the accelerated snowmelt.
But man-made global warming will put the final nail in the coffin, Scholhofer said. Larger patches could disappear within decades, and smaller ones “even shorter,” he estimated.
Around the world, permafrost is thawing. This is of great concern in the Arctic because of the potentially significant consequences. When the permafrost thaws, it releases large amounts of climate-warming carbon dioxide and methane into the atmosphere, further accelerating the rate of global warming. It can also cause the ground to soften and crumble, causing trees, buildings and other infrastructure to collapse.
Due to the relatively small amount of permafrost in Hawaii, such effects are likely to be minimal.
However, further warming and melting of Mauna Kea could have serious cultural consequences. Mauna Kea is a sacred place in Native Hawaiian tradition, a place of worship and abode of the gods. Among the gods associated with this mountain is the snow goddess Poliah.
But studies show that rising temperatures are jeopardizing snowfall on Mauna Kea. A 2017 study found that just a few more degrees of warming in Hawaii would “almost eliminate” snowfall by the end of the century.
And if Schorghofer is right, the permafrost will be gone long before then.
Its disappearance, he said, is “great evidence” of how climate change is reshaping the planet. And it’s a reminder that we may have little time left to study some of the natural wonders that are disappearing as the world warms.
“We’re just trying to study it before it disappears,” he said.
Reprinted from E&E News with permission of POLITICO, LLC. Copyright 2023. E&E News provides important news for energy and environmental professionals.
