Tag Archives: weather station

Eclipse meteorology

“Plan of Observations. -The meteorological observations proposed were especially directed towards the subjects of barometric pressure, air temperature, humidity, solar radiation, and wind velocity. The instruments located on the top of the tower were in charge of Mr. Rotch, and those at its base Mr. Upton.”

―Winslow Upton and A. Lawrence Rotch, Meteorological and other observations made at Willows, California, in connection with the total solar eclipse of January 1, 1889. Annals of the Astronomical Observatory of Harvard College, Vol. XXIX, 1893.

Diagram of the solar eclipse
Drawing of the total solar eclipse of January 1, 1889

The scientific instruments used during a solar eclipse include telescopes with a protective filter to reduce the brightness of the Sun to protect an astronomer’s eyesight. The earliest known image of the Sun taken by a camera was recorded in 1845. But it was still common for scientists to draw sketches with pencil and paper as it has been done for centuries. The above image is based on a number of photos taken with different exposure times. The short exposures record bright features but leave out many of the fainter ones. The longer exposures cause the bright features to be overexposed but reveals subtle details. The sketch above is a composite of these different photographs.

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Nor’easter

On March 2, 2018 a severe storm impacted southeastern New England. The storm was classified as a Nor’easter which is named for the characteristic strong winds from the northeast. During the storm our weather station recorded fifty-five wind gusts greater than 50 miles per hour. The two strongest were 62 mph at 1:48 and again at 1:50 pm.

wind speed graph
Average wind speed and highest wind gusts graph.

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The Weather Bureau in Providence

“In Philadelphia I dragged out a colorless and an unhappy existence till September, 1904, when to my delight I was ordered back to New England, and this time nearer the centre of civilization. (Of course by that I mean Boston, which is the “hub of the universe” the “Athens of America”, the “Centre of Culture”, and last but not least, the home of the humble baked bean and the sacred codfish). I was sent to Providence, R. I., and have remained here ever since and hope to continue my residence here. By a happy combination of circumstances I have lived in the classic halls of Brown University ever since my arrival in Providence. The location and environment are eminently satisfactory.”

―George Francis Field, “Harvard College Class of 1901.” June 1911

University Hall Weather Bureau
An instrument shelter on the roof of University Hall.

In addition to the weather station at Ladd Observatory there was another on the Brown campus. Located on the roof of University Hall it was operated by the U.S. Weather Bureau. The pole behind the chimney at left was likely used to support the anemometer, an instrument to measure wind speed.

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Thundersnow

During the Blizzard of Feb. 8-9, 2013 there were reports of thunder and lightning amidst the heavy snowfall and high winds. The lightning detector on the roof of Ladd Observatory recorded a great deal of activity late Friday night into Saturday morning with the peak occurring just before midnight. Most of the strikes were along the southern coast of Rhode Island, but some were observed about 350 miles to the south over the ocean. For more information about thunder snowstorms see Scientific American.

thundersnow
Plot of lightning strikes detected by our weather station during the Blizzard of Feb. 8-9, 2013. The activity was not as strong as a summer thunderstorm, but was unusual for this time of year and very rare for a blizzard.

The summit station at El Misti, Peru (19,200 feet)

“The night is passed at the hut, and the final ascent to the summit made on the second morning. This occupies several hours, as the animal stops to rest every fifteen or twenty feet at this altitude. On two occasions I was obliged to walk a short distance to cross snow which had drifted across the path, and realized the extreme difficulty of breathing during the exertion required.”

“The effect of the altitude upon me was chiefly to cause headache, sleeplessness and partial loss of appetite. On one occasion while at the summit I experienced a decided feeling of faintness for a short time.”

―Winslow Upton, “Physiological Effect of Diminished Air Pressure.Science, 27 December 1901

El Misti Summit Station

During the academic year of 1896-97 Prof. Winslow Upton took sabbatical from his work as Director of Brown University’s Ladd Observatory. He spent ten months at the new southern station of the Harvard College Observatory (elevation 8,050 feet) in Arequipa, Peru. His primary goal was to measure the geographical position of the station before astronomical observations could commence.

During this time he also made four ascents to the summit of the dormant volcano El Misti, which was the site of recording instruments (pictured above) maintained by Harvard. At the time it was the highest meteorological station in the world at an elevation of 19,200 feet.

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