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T. H. MacDONALD

Abstract

Tests were made of the effect of several variables on the performance of the Eppley pyrheliometer. The tests showed: (1) How the output increased with decreasing ambient temperature; (2) how output varied with angle of incidence of collimated radiation; (3) that output decreased about 5 percent when receiver was exposed in the vertical plane, but that complete inversion from the horizontal had no significant effect; and (4) that a few water droplets on the glass envelope did not influence output. In addition, spectral transmission data, from National Bureau of Standards tests, are shown.

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S. FRITZ
and
T. H. MacDONALD

Abstract

Normal-incidence solar radiation values were measured during the IGY at the South Pole and Little America (Antarctica), at Mauna Loa (Hawaii), Tucson (Arizona), and Blue Hill Observatory (Massachusetts); some results are given in tables and graphs. Essential differences among them are discussed. The radiation data at Tucson and Blue Hill are appreciably lower than at the other stations. The radiation, corrected for solar distance, is similar at the Antarctic stations to the radiation measured at Mauna Loa. However, the actual measured values in summer are higher at the South Pole than at Mauna Loa, because the sun is closer to the earth in the Southern Hemisphere summer. The “extrapolated turbidity factor” is over 2.5 at Tucson and Blue Hill, but averages 2.0 or less at the other stations with the lowest values of about 1.5 at the South Pole.

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T. H. MACDONALD
and
NORMAN B. FOSTER

Abstract

A new system developed for calibrating the horizontal incidence pyrheliometer is described. The pyrheliometers to be calibrated are exposed simultaneously with a standard pyrheliometer in an integrating sphere. Calibrations are made by comparing voltages developed by the instruments undergoing calibration with those of the standard pyrheliometer. Calibration of the standard pyrheliometer is based on comparisons with the Smithsonian Institution pyranometer, both out-of-doors on clear days and within the integrating sphere. Advantages of the new system include reproducibility of the calibration within less than one percent. This is due to the reproducibility of the radiation field in the integrating sphere, in which there are relatively small variations in ambient temperature. The calibrations can be done much more rapidly and accurately than was formerly the case when the work was done out-of-doors; clear skies and minimum atmospheric pollution were necessary conditions previously.

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NORMAN B. FOSTER
and
T. H. MACDONALD

Abstract

The following devices for simplifying the operation of the Abbot Silver Disk Pyrheliometer are described: (1) an automatic shutter, (2) a simplified heating and cooling timing sequence and (3) an improved method of reading the pyrheliometer thermometer. The authors also describe their experience in automatically recording the silver disk temperature by means of a thermocouple, amplifier, and recorder.

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P. Joe
,
S. Belair
,
N.B. Bernier
,
V. Bouchet
,
J. R. Brook
,
D. Brunet
,
W. Burrows
,
J.-P. Charland
,
A. Dehghan
,
N. Driedger
,
C. Duhaime
,
G. Evans
,
A.-B. Filion
,
R. Frenette
,
J. de Grandpré
,
I. Gultepe
,
D. Henderson
,
A. Herdt
,
N. Hilker
,
L. Huang
,
E. Hung
,
G. Isaac
,
C.-H. Jeong
,
D. Johnston
,
J. Klaassen
,
S. Leroyer
,
H. Lin
,
M. MacDonald
,
J. MacPhee
,
Z. Mariani
,
T. Munoz
,
J. Reid
,
A. Robichaud
,
Y. Rochon
,
K. Shairsingh
,
D. Sills
,
L. Spacek
,
C. Stroud
,
Y. Su
,
N. Taylor
,
J. Vanos
,
J. Voogt
,
J. M. Wang
,
T. Wiechers
,
S. Wren
,
H. Yang
, and
T. Yip

Abstract

The Pan and Parapan American Games (PA15) are the third largest sporting event in the world and were held in Toronto in the summer of 2015 (10–26 July and 7–15 August). This was used as an opportunity to coordinate and showcase existing innovative research and development activities related to weather, air quality (AQ), and health at Environment and Climate Change Canada. New observational technologies included weather stations based on compact sensors that were augmented with black globe thermometers, two Doppler lidars, two wave buoys, a 3D lightning mapping array, two new AQ stations, and low-cost AQ and ultraviolet sensors. These were supplemented by observations from other agencies, four mobile vehicles, two mobile AQ laboratories, and two supersites with enhanced vertical profiling. High-resolution modeling for weather (250 m and 1 km), AQ (2.5 km), lake circulation (2 km), and wave models (250-m, 1-km, and 2.5-km ensembles) were run. The focus of the science, which guided the design of the observation network, was to characterize and investigate the lake breeze, which affects thunderstorm initiation, air pollutant transport, and heat stress. Experimental forecasts and nowcasts were provided by research support desks. Web portals provided access to the experimental products for other government departments, public health authorities, and PA15 decision-makers. The data have been released through the government of Canada’s Open Data Portal and as a World Meteorological Organization’s Global Atmospheric Watch Urban Research Meteorology and Environment dataset.

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