In a word, it's rain. An extraordinary amount of rain has fallen in and around Death Valley this year, around 300% of what is normal. That sounds more dramatic than saying that 4.8 inches has occurred so far. A "normal" year to this point would see about 1.5 inches. And the rain did not fall in Death Valley alone. Death Valley is the lowest basin in a very large drainage system, and the surrounding landscape received even more. It was primarily the result of two events: the remnants of Hurricane Hilary in late August 2023 provided the floodwaters that resulted in the first iteration of the lake. In the hot months that followed, much of the accumulated water evaporated, but then the first week of February brought an atmospheric river storm to California that rejuvenated the shrinking lake. We were lucky to arrive a week later.
This kind of thing doesn't happen often. Some water was present on the valley floor in 2010, and earlier in 2005. But both of those years, floods had damaged the road to Dante's View so I haven't had a birds-eye view of the lake in at least three decades. It was fantastic.
When I and my students travel to Death Valley they get a packing list, but I tend not to put 'kayak' or 'raft' on that list. But we knew the lake would be there, so our long-term friend and trip volunteer Ryan actually packed one, so we had the spectacle of the Hollister family rafting Death Valley.The lake has been in the news, so we weren't surprised to see a multitude of tourists gathered in the parking lot at Badwater. I didn't think they'd all opt to go walking in the slimy muddy salty water, but you can see that they did. I was much happier to have stopped along the lake a mile to the south where there was no one but ourselves.
It was along that quiet shoreline that I was able to hear the echoes of a distant past when Death Valley was a watery paradise rather than the hellscape it is today (albeit a very beautiful and dramatic hellscape). That is what is revealed by the geological evidence scattered along the normally parched lake margins.At the south end of Death Valley there is an old basalt cinder cone with a strange name: Shoreline Butte. In the picture above, the shoreline terraces are highlighted by the "Superbloom" of 2016 (with all the rain this year, there is at least a possibility of another superbloom in a few weeks). Each of those horizontal terraces was carved by wave action. This and other clues scattered around the margins of the basin are evidence of a lake that existed here for thousands of years. It was as much as 600 feet deep, and more than 100 miles long.
Where did all that water come from?
Along Beatty Cutoff Road, there is a beach berm covered by rounded flattened pebbles. This was along the northern shoreline of Lake Manly when it was 450 feet deep. |
Pluvial lakes of Eastern California. Source: Philip Stoffer of the U.S. Geological Survey |
Ice-age Owens Lake reached a depth of 300 feet and spilled over into China Lake, then Searles Lake, Panamint Lake, and finally Lake Manly in Death Valley. These ice-age bodies of water are called pluvial lakes. The cooler wetter conditions allowed two other river systems to contribute water, the Amargosa River out of Nevada, and the Mojave River out of the San Bernardino Mountains in Southern California. There may have even been a temporary connection with the Colorado River, which resulted in one of the most surprising aspects of Death Valley biology: fish!
Salt Creek Pupfish from the middle of Death Valley |
Yes, there are fish in Death Valley! In fact, there are several species. They survive in widely scattered springs and short stretches of perennial streams that exist in the desert. The pupfish (cyprinodon) are of particular interest because they probably once were a single widespread species, but when isolated in springs that were either hot or cold, or salty or fresh, they were forced to evolve or perish. Today there are four species in the confines of the park and several others in outlying areas, especially the Owens Valley and Ash Meadows in Nevada. I've found their story to be intriguing and I've written about them a number of times. These diminutive fish survive in the saltiest and hottest water of any known fish species.
Mammoth bones on display at the Shoshone Museum, east of Death Valley |
Imagining this vast ice-age lake meant led to another vision of past worlds. In the early 1980s, some students on a geology field trip were hanging out near their camp in the Shoshone area when they discovered bones sticking out of a gully wall. These bones proved to be specimens of Columbian Mammoths and other ice age mammal species (the specimens are currently on display in the Shoshone Museum east of the park). The Death Valley region was a much cooler and more verdant environment during the ice ages, and the shoreline of Lake Manly was populated by grazing animals including the aforementioned mammoths, camels, horses, bison, and the carnivores that would have preyed upon them, including the large cats and perhaps relatives to today's wolves and coyotes.
Looking at the shore of Lake Manly at Badwater from a vertical mile above from Dante's View |
1 comment:
Love this post and "the magic of geology." Well done!
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