OK, I’d been sent off to work in the salt mines by a comment on the Ostia Antica thread by tckev.
One thing lead to another, and I found myself looking at the Great Salt Lake history in Utah.
This needs a lot more work than I can hope to put into it right now, but would be a great project for anyone with an interest. It’s pretty straight forward.
The Great Salt Lake is very shallow, so the area moves back and forth A Lot with rainfall changes. My thesis is that when we are cooling, we have a load of extra rain as it is what deposited all the heat at altitude when it was water vapor, then condenses and falls.
If this is true, one expects to find a load of rain during “cooling times” and with less rain during “heating times”, modulo a certain amount of lag time and edge effects at inflection points.
So I went off to read about The Great Salt Lake, and found that Utah had put in a major pumping station specifically to reduce the water level (that peaked in 1986) as it was causing unexpected flooding problems. Then the pumps got turned off and have never been needed again. (As we warmed out of that cold 1960-1980 time period).
West Desert pumping project
Record high water levels in the 1980s caused massive property damage for owners on the eastern side of the lake, and started to erode the base of Interstate 80. In response, the state of Utah built the West Desert pumping project on the western side of the lake, featuring a pumping station (41°15′9.28″N 113°4′53.31″W) at Hogup Ridge, containing three pumps with a combined capability of releasing 1,500,000 US gallons per minute (95 m3/s); a 4.1-mile (6.6 km) outlet canal, an inlet canal, which allowed water from the Newfoundland Evaporation Basin to return to Great Salt Lake; 25 miles (40 km) of dikes, and a 10-mile (16 km) access road between the railroad town of Lakeside and the pumping station.
The project was designed to increase the surface area of the Great Salt Lake, and therefore the rate of evaporation. The pumps released Great Salt Lake’s waters into the 320,000 acre (1300 km²) Newfoundland Evaporation Basin in the west desert. A weir in the dike at the south end of the Newfoundland Mountains regulated the level of water in the basin, and returned salty water from the basin to the main body of Great Salt Lake.
At the end of their first year in operation, the pumps had released around 500,000 acre feet (0.6 km³) of water. The project was shut down in June 1989, as the lake had dropped almost 6 feet (2 m) since reaching its peak in June 1986 and March 1987. The Utah Division of Water Resources credits the project with “over one-third of that decline.” In total, the pumps released 2.73 million acre feet (3.4 km³) of water while they operated. Although the pumps are not currently in use, they are maintained in the event the lake rises to those levels again.
But recently we’ve had an increase in rain in Utah. And we’re starting a cooling trend. Sooo….
The reasonable prediction is that, again with a bit of lag time, The Great Salt Lake ought to start rising again. Perhaps even enough that within a decade or so we could be looking at restarting those pumps…
A great small research project would be to take the recorded lake level history and plot it against the known temperature cycle of the PDO and see what the correlation and lag time might be. A “follow on” would be to see the level recently and map it against the recent temperature cycles to see if the historic pattern has been broken (and perhaps indicating that the thermometers are just not quite right now as they have lost their hook to the climate reality of the basin…)
If you click on the map you will get a truly gigantic one that has a readable legend. At this scale, just note that the shades of blue on the lake are indicating three historic levels. The 1963 historic low of 4191 feet (ASL), the average, and the 1986 high of 4212 feet (ASL).
In particular, notice those dates. 1963 was about a decade after the warm period had ended. We were hot in the 1930s – 40s, and started a cool off into the 1950s. Then, just about 1963 – 66 we started a very cold turn. That kept going through the 1970s and into the slightly warming 1980s. So, per my thesis, rain was falling and accumulating during that cooling cycle. Then, in the 1980s, we left the “new ice age” scare behind and started a bit of warming. Just in time for lake to crest in 1986. Since then, as we warmed, the lake has been dropping (even with the pumps turned off). Until now. So if we have entered a ‘cooling trend’ we ought to see more rain falling around Utah, and then with a bit of a lag, a rising Great Salt Lake.
News of note? From 10 August 2010:
Storm shatters rainfall records, floods homes across Utah
“There was 2 feet of water in the room in 10 seconds,” said the 16-year-old after a massive downpour hit his Draper neighborhood. “It got up to 41/2 to 5 feet deep before it stopped. We had to break a door down on the other side of the house to let all the water out.”
The potent storm shattered rainfall records for the date, caused havoc with roads in southern Salt Lake and Utah counties, prompted flash flood warnings in southwestern and central Utah and resulted in scattered power outages.
“We have had big storms before, but not with this result. The water was coming down Pioneer Road and right into our house,” she said. “There was water coming out of manholes. There was nothing we could have done to protect our house.”
But the sheer amount of rain that fell in a such short time — .39 inches in five minutes — may have been the main culprit. Debris flowed down Corner Canyon Thursday because the slope has not recovered from the fire, said Brian McInerney, hydrologist with the National Weather Service in Salt Lake City. A half-inch of rain in one hour is enough to produce mud on such slopes, but this storm was much juicier.
So earlier this year they were getting dumped on.
But what was happening at the peak of the “warm cycle”?
Drought Conditions in Utah During 1999-2002: A Historical Perspective
So, just at the peak of temperatures (1998) and for 3 years after, we have a drought…
Then it goes on to give some history. Floods during the “cooling years” from 1952 to 1984, then droughts during the very hot 1930-36 window that brackets the ‘hottest year ever’ in the USA of 1934. It would be very interesting to find out if 1896-1905 was a hot time. It’s the wrong part of a 60 year cycle, but then again, we don’t know if the PDO is a regular 60 years all the time. 1988-1993 fits the hot cycle thesis, but 53-65 and 74-78 don’t quite. I think we need some better graphing analysis done on these individually. There may well be a faster period cycle on top of the longer period cycle that makes simple drought / flood dates less than an ideal metric. The “average” as indicated by lake level may be valuable here.
Utah’s weather is prone to extremes—from severe flooding to multiyear droughts. Five major floods occurred during 1952, 1965, 1966, 1983, and 1984, and six multiyear droughts occurred during 1896-1905, 1930-36, 1953-65, 1974-78 (U.S. Geological Survey, 1991), and more recently during 1988-93 and 1999-2002. The areal extent of floods generally is limited in size from one to several watersheds, whereas droughts generally affect most or all of the state. Southern Utah, in particular the Virgin River drainage basin, began experiencing drought conditions during the winter of 1998-99. By 2000, drought conditions were evident throughout all of Utah. The current drought (1999-2002) is comparable in length and magnitude to previous droughts; however, with population growth and increased demandfor water in Utah, the general effect is more severe.
During2002, the fourth straight year of nearly statewide drought conditions, some areasof Utah experienced record-low streamflows. Several record-low streamflows occurred in streams with records dating back to the 1900s. The U.S. Geological Survey (USGS) uses streamflow data from eight long-term streamflow-gagingstations for comparison of hydrologic conditions in Utah (fig. 1).
Matching this chart (from the same link) to the PDO and / or temperature graphs might be enlightening:
And, for folks who like “the data” we have this link:
where you can look up rainfall measurements all around the area. An “eyeball” of the chart looks to me like 2010 annual totals are much higher than 2007 annual totals, but it really needs more years of data and a proper graphing.
No, nowhere near a proof of anything. But yes, it’s a very intriguing thing to investigate.
I’ve just turned up more of them than I can do right now. But I really do think this one has a great deal of promise. Rather like the “Salt Drinking Lake” that Adolfo pointed me at some time back. Perhaps he will post the pointer to that article again here … hint hint ;-)
If rainfall IS the correct barometer of cooling / warming cycles, then having a few shallow salt lakes around the world might just be the best proxy yet for a heat gain / heat loss indicator.