Series (Travel): Death Valley

Death Valley, Part 1: Why is it So Damn Hot?

This is Part 1 of a multi-part series about Death Valley. For the next installation (when available), CLICK THIS LINK. Thanks for reading!

Why is it So Damn Hot?

Why is it so damn hot in Death Valley? Let’s take a ride to Outer Space, for our first clue. Looking down from Space at the Pacific Ocean, you may notice a giant swirl. A gyre, as they call it. It slowly spins clockwise, forcing warm water up the coast of East Asia, where it gradually cools down. Then the gyre washes around the shivering Aleutians, and pulls the now frigid current down the west coast of North America.

Anyone who’s used a teapot knows that frigid water doesn’t evaporate as readily as warm water. Thus, the storms coming off the frigid Pacific Ocean, hitting the west coast of North America, pack less moisture than the storms coming off the warm Pacific Ocean, that strike the east coast of Asia.

So they rain out quickly along our coastline, leaving little rain for inland areas. This is why we have deserts that extend from the east side of Washington state all the way down to the east side of Southern California.

And then there’s the phenomenon called the enthalpy of vaporization. It was discovered by a man with a lisp. Enthalpy is the heat required to turn water into vapor, forcing it to evaporate. Strangely, this heat gets stored in the water molecules of the vapor. And as chilly as the Pacific Ocean water is, off the west coast of North America, it still gets warm enough for some enthalpy-generated evaporation to occur. This enthalpic heat gets stored in the resulting water vapor.

Heat rises, carrying the vapor upward. At higher altitudes, the vapor cools to the point of condensing back to liquid, in the form of tiny water droplets. And when this happens, the heat the vapor was storing is released into the air. Meanwhile, the tiny water droplets constellate together, forming visible clouds.

Water vapor and clouds are drawn toward California from the Pacific by prevailing westerly winds. Meanwhile, the Coriolis effect curls the clouds into a spiral pattern, which we identify in satellite images as a storm.

When the water vapor from a storm collides with the coastal ranges of California, such as the Diablo Range, the Santa Lucia Range, and the Temblor Range, winds push it upward, over the slopes. And as this moist air is pushed upward, it cools at the rate of one degree Fahrenheit, per 1,000 feet of altitude gain.

The coastal ranges tend to be low-lying. Just a few thousand feet. So not much cooling can occur there. Nonetheless, enough cools to add a few extra clouds to the storm, while releasing stored heat.

The warmed air from the released heat pushes eastward over the mountains and down the other side, which helps to warm up the valleys on the other side. In this case, California’s Central Valley. But like I say, it’s not a whole lot of warmth, because the coastal ranges are so low.

But the next range this air hits is much higher. This is the mighty and formidable Sierra Nevada Range, with 14,505 foot Mount Whitney, the highest point in the contiguous United States, as its centerpiece. The moist air cools much more, as it rises up the western slope of the high Sierras. Many new clouds form, in a phenomenon called orographic lifting, and as they form, they release a tremendous amount of stored heat from the condensing water vapor.

As I said, moist air cools at the rate of one degree per thousand feet of uplift. But dry air warms at the rate of five degrees per thousand feet of descent. The clouds that form on the western slope of the Sierra Nevada tend to rain and snow themselves out before they reach the crest of the mountains. That’s because there isn’t as much moisture in the storms that hit the west coast of North America, as there is in the storms that hit the east coast of Asia.

The result is relatively warm, dry air at the crest of the Sierra Nevada, that descends down the eastern slope. And as it descends, it heats up more rapidly than it cooled, due to its dryness. And so the air that gets pushed over the mountains is warmer on the eastern side than it was on the western side, at equivalent altitudes.

The next mountain range in line for some of this air, is the Argus Range, across from the Owens Valley. Here, the moderately tall Argus Peak (6,562 feet) and Maturango Peak (8,839 feet), squeeze out a few more clouds, rain, and heat from the storm.

What few clouds remain, scud across the Panamint Valley, 22 miles east toward the Panamint Range. This range is a tall wall, with its 11,049 foot Telescope Peak pushing the storm air high upward for a fourth time since it first breached the shores of California’s coastline.

Usually there is little moisture left in the air by the time it reaches the Panamint Range. But what remains is wrung out like a semi-damp washrag. Rarely does any moisture escape to the valley on the other side.

Which is Death Valley.

And that is why the valley on the other side of the Panamints is so damned hot. Death Valley, at its lowest point, is 282 feet below sea level. That’s at Badwater Basin, and Badwater rests just 16 miles east of Telescope Peak. Thus, super-dry air descends rapidly, more than 11,000 feet from Telescope Peak to Badwater Basin, heating up 56 degrees before touching bottom.

Badwater Basin from Dante’s View, with Telescope Peak towering above. I’ve visited Death Valley three times since 2007, most recently a few weeks ago. This photo is from November 2007.

But orographic lifting, and its heating effect over four mountain ranges, only explains part of the reason why it’s so damn hot in Death Valley.

It hardly ever rains in the Valley of Death. Badwater Basin only sips an average of 1.50 inches of precipitation from the sky, per year. So the sky is usually so clear and dry, it invites the most intense, unfiltered rays of the Sun to strike the valley floor.

And most of the valley floor is dark colored, allowing it to absorb heat from the Sun’s rays almost as efficiently as an asphalt highway.

This heat rises, but the tall mountains that surround the valley prevent much of the heat from escaping. Thus, it keeps recirculating upon itself. This is similar to the heating effect of the Sun on the interior of a car, if it’s parked outside with all the windows rolled up.

Badwater Basin is 2,538 miles north of the Equator, which is 40% of the distance from the Equator to the North Pole. But in spite of such a northerly latitude, Death Valley is the hottest spot on the planet. This is due to all the climatic and geographic conditions I described above, that contribute to its heating and that prevent its cooling.

On July 10, 1913, thermometers at Death Valley’s Furnace Creek boiled up to a record 134.1 degrees Fahrenheit. This is the hottest atmospheric temperature ever recorded on Earth. In 2020 and 2021, temperatures reached 130F, which are the fifth and sixth hottest days ever recorded on Earth. And on July 15, 1972, the highest ground surface temperature ever recorded on our planet, sizzled at Furnace Creek. The Sun heated the soil to a sneaker-melting 201F.

In 2001, the maximum temperature reached at least 100F for 154 consecutive days, which is yet another worldwide record for Death Valley.

Death Valley offers some relief from the heat, though. Its average high temperature in December is only 66F, with an average low of 41F. But in July, its hottest month, the average high and low are 117F and 91F, respectively. This affords little overnight relief for those who’ve baked in the Sun all day.

Death Valley is so frequently the hottest spot in the United States, that meteorologists routinely omit it when they report the highest temperatures in the nation. After all, nobody wants to keep hearing the same news over and over again. But if you assume that Death Valley is the warmest spot in the country, each and every day during the summer, rest assured that you’ll usually be right.

And now you know why.

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14 replies »

  1. A lot I didn’t know. I think they had some flash-flooding recently?

    Heat is my bane. I have to work at it to build up some heat tolerance in summer (90F is scorching here). The hottest air temperature I’ve ever experienced was (a very smoggy) 117F, near the city of Riverside while I was in college. I remember thinking that I might pass out after going up some stairs. Mercifully, there was AC. I can’t even imagine it being 10 or more degrees hotter. 130F!!!?

    Liked by 2 people

    • Yes, they had flash-flooding last fall, which closed a lot of roads. Most everything has opened back up, but the boardwalk to the Salt Creek pupfish was heavily damaged, and is still closed to the public.

      Some people do better in cold than hot, and vice-versa. I’m vice-versa. Or arsy-versy. For several years I delivered mail in Palm Springs, where 117F in the summer is very common. Whenever the temperature did not get past 105F, I considered it to be a cool summer day.

      Liked by 1 person

  2. And now I feel smarter, thank you, science teacher. πŸ™‚ Death Valley seems to be a very appropriate name. I can’t imagine 154 days straight of 100 degree temps, sounds like Texas a bit.
    So if I want to visit Death Valley, I should go in December!

    Liked by 2 people

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