Salt flats
at Badwater, -282 feet. The snowcapped mountain in the distance is Telescope
Peak, 11,049 feet.
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How bad
could it be? On our recent trip to Death Valley, we made the rather mandatory
pilgrimage to Badwater, the lowest point in North America at -282 feet (86
meters). Although the hottest temperature ever recorded on planet Earth was
measured at Furnace Creek Ranch in 1913 (56.7°C; 134°F), it is known that
Badwater is often 2 degrees hotter. That's hot. Really hot.
I've
regularly worked and played in temperatures as high as 105°F without ill effect
at home in the Great Valley of California. I floated down the Colorado River in
August of 2013 where temperatures soared as high as 118°F, and I realized that
I could have been in trouble if we didn't have the river to dip in every few
minutes (because it flowed from deep within Lake Powell, the water temperature
was around 48°F even many miles downstream). The hottest moment I've ever
experienced was in the aforementioned Death Valley when we had an occasion to
be there in late May, and an early heat wave shot temperatures to a near record
122°F. It was simply intolerable outdoors...we retreated to the motel room
until the sun went down before emerging to seek dinner. People no doubt adapt
to such conditions, but it can't be pleasant.
Alluvial
fan just south of Badwater. The terraces on the fan are fault scarps,
indicating the role of faulting in the subsidence of Death Valley.
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Standing
at the lowest point in North America does cause one to consider other low
places on the planet. The National Park Service provides a handy guide on
interpretive signs and on their websites. They note that all of the low places
also tend to be exceedingly dry and hot, and that the source of the low
elevation is generally tectonic in origin. Those low points are as follows:
Dead Sea
(Jordan/Israel) -1360 feet (-414 m)
Lake Assal
(Djibouti, Africa) -509 feet (-155 m)
Turpan
Pendi (China) -505 feet (-154 m)
Qattara
Depression (Egypt) -435 feet (-133 m)
Vpadina
Kaundy (Kazakstan) -433 ft (-132 m)
Denakil
(Ethiopia) -410 ft (-125 m)
Laguna del
Carbón (Argentina) -344 ft (-105 m)
Death
Valley (United States) -282 ft (-86 m)
Vpadina
Akchanaya (Turkmenistan) -266 ft (-81 m)
Salton Sea
(California) -227 ft (-69 m)
Sebkhet
Tah (Morroco) -180 ft (-55 m)
Sabkhat
Ghuzayyil (Libya) -154 ft (-47 m)
Lago
Enriquillo (Dominican Republic) -151 ft (-46 m)
Salinas
Chicas (Argentina) -131 ft (-40 m)
Caspian
Sea (Central Asia) -92 ft (-28 m)
Lake Eyre
(Australia) -49 ft (-15 m)
The Black
Mountains provide the backdrop to Badwater. They rise steeply more than a mile
above the salt flats.
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Looking at
this list, it is clear that the Dead Sea is in a class by itself as far as low
elevations are concerned. At nearly 1,400 feet below sea level, it is unique in
the world. To find anything deeper, we have to reach back into the depths of
geologic time. The Strait of Gibraltar is narrow and shallow, and is the only
connection between the Mediterranean and any other ocean. What would happen if
it ever separated the two oceans? It's not totally idle speculation...it turns
out that this actually happened, about six million years ago. The speculation
began when vast amounts of salt, gypsum and anhydrite deposits were discovered
beneath the seafloor sediments of today's Mediterranean Sea.
When the
cutoff occurred, the Mediterranean immediately began to dry up. And dried more.
And then even more. The level of the sea dropped precipitously. It dropped past
the 1,000 foot level. And then 2,000. And it kept going. Until the level of the basin reached 15,000 feet below sea level. Three miles below sea level. The implications
are staggering in many ways. The Nile and Rhone Rivers would have started
cutting deep channels far below their normal level. In places, the subsequent
sedimentary layers hide canyons that were once 8,000 feet deep (The Grand
Canyon, for comparison is 5-6 thousand feet deep).
The
climate changes would be extreme. Air sinking into the basin would increase
temperatures at the dry adiabatic rate of 5.5°F per thousand feet. That amounts
to conditions at the lowest reaches of the Mediterranean Basin that would be
70°F higher than they would be at sea level. In this desert environment,
summertime temperatures could reach 176°F. No organisms could survive at these
levels except for a few thermophiles. This is a place no human could or would
be able to venture.
And
imagine the end. Imagine the moment that the Atlantic Ocean began seeping over
the Strait of Gibraltar. Seepage that turned into a torrent, and then a torrent
that turned into a flood, and a flood that turned into a deluge beyond
imagining. Some calculations suggest flows equivalent to 1,000 Amazon Rivers at
once. The entire ocean basin could have filled in between a few months to two
years. Sea level would have risen as much as 30 feet per day. This event is called the Zanclean Flood.
All in all, this place would have been hell on Earth, at least until the waters came...
All in all, this place would have been hell on Earth, at least until the waters came...
PS: The Rhone River, not the Rhine. Correction made, thank you Olivier Malinur.
1 comment:
The hottest I've ever felt at Furnace Creek was 129. Once you get over 105 or so you really can't tell the difference. It's just hot.
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