William Reid

Nope --- we will "never know for sure" on most of these Death Valley records! And as "The Snow Wizard" mentions, the Greenland Ranch thermometer shelter was indeed properly exposed ---- it was very, very well-exposed, based on the photographs available. You might be interested in a recent blog entry by me regarding the Greenland Ranch weather station and the early observers, including Denton --- http://stormbruiser.com/chase/2017/11/30/unravelling-death-valleys-134f-temperature-record-part-6-observer-oscar-a-denton/ The current Death Valley weather station is NOT as well exposed as the Greenland Ranch station was, apparently. A gradual increase in vegetation (bushes and trees) and buildings to the south of the DV station in the past 20-40 years has decreased the air movement through the station site. Slower wind speeds through the current Death Valley site promote warmer maximums because air heated along the bare ground is permitted to build a little more, comparably. Since the current station site has managed "only" 129F since 1961 (despite the poorer ventilation above bare ground), how does one explain maximums of 129, 130, 131 and 134F in July, 1913, at a better-exposed location above sod (especially when these maximums are not supported by maximums at surrounding stations)?

Hi Scott --- the 129F at GR on July 18, 1960, is very suspect when the GR maximums for this heat wave are compared to maximums at Cow Creek, just three miles up the road and just 20 feet higher. Cow Creek summer maximums were typically a degree or two warmer than at GR. From my blog, here are the daily maximums from July 16 to July 20: Cow Creek maximums for the hottest period , from July 16 to 20: 125, 126, 126, 126, 126 and for Greenland Ranch for the same period: 124, 124, 129, 124, 124 I need to dig to see if a thermograph was running in the GR shelter during this timeframe. A thermograph in a temporary shelter at Badwater showed "only"128F on July 18. GR is/was almost never hotter than Badwater. These discrepancies strongly suggest the 129F max at GR in July 1960 is not authentic. A recorded max of 128F at Cow Creek was officially rejected by the USWB in the 1950s, but I don't think the 129F at GR in 1960 has been invalidated. It is my contention only that the most reliable maximum at GR from 1911 to 1961 is 127F. Below is more about the July 129F max at GR, and you can read all about it and see some fancy charts here (halfway down for July 1960): http://stormbruiser.com/chase/2016/08/23/unravelling-death-valleys-134f-temperature-record-part-4-historic-heat-waves/ The form for Greenland Ranch for July, 1960, shows a maximum of 129F on July 18th. The entry appears to be erroneous when a comparison is made between Greenland Ranch and Cow Creek maximums on the other days this month. Cow Creek, only three miles up the road, routinely averaged a degree or so warmer than Greenland Ranch on July afternoons from 1935 to 1960. For July, 1960, the average maximum at Cow Creek was 119.5F, 1.4 degrees (F) warmer than the 118.1F at Greenland Ranch. Of the 31 days for July, 1960, the two stations had an identical maximum temperature on only one date. On 11 dates, Cow Creek was warmer by one degree (F), and on 13 dates, Cow Creek was warmer by two degrees. Cow Creek’s maximum was warmer than that at Greenland Ranch by three degrees on three days. Greenland Ranch reported a warmer maximum three times: twice by one degree, and once by three degrees. On the 18th, Greenland Ranch reported 129F and Cow Creek reported 126F. The differences in maximum temperature between the two stations for the hot spell from the 13th to the 23rd: Cow Creek warmer by 1, 0, 1, 1, 2, -3, 2, 2, 2, 3, and 1. Cow Creek maximums for the hottest period , from July 16 to 20: 125, 126, 126, 126, 126 and for Greenland Ranch for the same period: 124, 124, 129, 124, 124 Why would Greenland Ranch suddenly be the warmer station on the 18th, and by three degrees? It seems likely that the Greenland Ranch maximum thermometer was misread by the observer. The “set max” temperature here at about 4 p.m. on the 18th was 123F, which does little to support the 129F report. Usually the temperature at 4 p.m. is just a couple of degrees lower than the day’s maximum. At Cow Creek on the 18th, the maximum was 126F and the “set max” temperature at about 4 p.m. was 125F. Since the 129F at Greenland Ranch on the 18th this month is suspect, the maximum for this date is reduced to 124F, and the maximum for the month at Greenland Ranch is changed from 129F to 124F. The highest reliable maximum temperature at Greenland Ranch for its 50 summers from 1911 to 1960 remains at 127F.