The True Story of Mount Rainier “Mang Tan”

As many readers of the blog know, I often provide fact-checking for the Seattle Times’ exaggerated and often inaccurate articles on climate change.

Unfortunately, the Seattle Times has moved into a climate change advocacy role, often exaggerating the impact of global warming. They often fail to provide reliable information to their readers on this important topic.

In yesterday’s online newspaper, they had a front page story written by their columnist, Danny Westneat: Mount Rainier is melting. Can anything be done to prevent it?

As you can imagine, they are talking about glaciers on Mt. Rainier. The story refers to a new National Park Service report that “penetrates” and talks about a dramatic reduction in glacier ice volume.

The message in the paper is clear: The Rainier glaciers are now retreating rapidly, and anthropogenic CO2 emissions are to blame. We need to act now.

“It’s climate change before your eyes.”

“We really have to focus on how we release carbon into the air.”

This is a very deceptive post designed to convince us that a distinctive aspect of our region is being lost to human carbon emissions.

The truth is that Rainier’s thaw is largely natural, with human carbon emissions being a small part of the story.

Although the story is said to be motivated by a new report by Scott Beason and associates of the National Park Service (a very good piece, may I add), this paper NEVER mentioned that much of the glacial loss on Rainier has little to do with human-caused climate change due to increased CO2, and proof of this claim is found in the report itself. .

See Figure 6 of the report, which shows the change in glacial area on Mount Rainier since 1895 (below). The glacial area has decreased from about 130 square kilometers to about 75 square kilometers. Note that most of the ice melt was between 1895 and 1970, a period when there was very little human-caused global warming.

Ice volume tells the same story (see below)

Viewing the ice volume of the largest glacier Rainier (Emmons) shows that nearly ALL losses occurred between 1895-1915.

There is a great deal of evidence that the impact of human greenhouse gas emissions was only significant after about 1980. Therefore, much of the loss of the Rainier ice must have been natural.

Actually, we have a good idea of ​​what happened. From about 1350 to 1850 AD, a large part of the Northern Hemisphere was in the Little Ice Age, a period of cold temperatures and more snowfall. There are many proposed mechanisms, including changes in solar radiation and shifts in ocean currents, all of which are caused by natural processes. Beginning in the late 1800s, the world and our region began to warm, glaciers began to melt and retreat… as shown in the image above.

Don’t get me wrong: global warming due to our greenhouse gas emissions is gradually warming the planet, and such warming will contribute to the melting of ice over the past few decades. But that contribution is quite modest compared to natural variability, something the article does not address.

But there is much more.

The extent of warming that has occurred in Rainier (and our region in general) is relatively small due to the presence of the Pacific Ocean, which has significantly slowed warming of the region. And this is especially true of the windward (west) side of the Cascades, of which Rainier is a part.

We can show this unambiguously using the observations at Paradise on Mt. Rainier, located about 5000 ft ASL. Below is a chart of annual temperatures in Paradise from 1917 to 2022, including the period after the end of the Little Ice Age.

NO HEAT. In fact, the trendline shows a slight cooling off. This hardly suggests that a major warming would cause a major glacial melt. There are periods when temperatures are slightly warmer and cooler, but there is no general trend.

I should note that there was little change in precipitation over the entire period at this location.

But let’s go one step further. Glaciers are controlled by replenishment in winter and melting in summer, so consider summer temperature trends (June, July, August) at Paradise Ranger Station (below) . There is a small upward trend around 1°F. Less ocean influence in summer.

The long-term perspective is crucial for looking at such climate data. Imagine I just graphed Rainier summer temperatures over the past 30 years (see below).

YIKE. Now the temperature has warmed to 4F! People will start panicking.

Key point

A detailed look at the excellent National Park Service report and long-term glacial and meteorological data suggests the following story.

There has been a significant loss of glacial area and volume on Mount Rainier during the past 130 years.

Most of the loss is natural and occurs before human-caused global warming can be significant.

Mount Rainier, the lower reaches of the warming Pacific Ocean, has experienced very little year-round warming since the early 20th century. Summer warming has waned over the past century, but there has been some short-term warming over the past decades.

I believe a reasonable conclusion to all of this is that most of the ice loss on Rainier over the past century has been natural, but that anthropogenic warming is likely to be contributing a modest part to this. the loss of ice over the past few decades.

I wish Seattle Times reporters like Danny Westneat would take the time to give their readers an accurate, nuanced understanding of what’s going on. And no, I don’t think his idea of ​​putting tarps or glass beads on a glacier is a good idea.

Finally, let me note that it’s SCIENCE in Paradise this morning. Mother Nature is telling us something.