Messrs. Stewart and Jörgensen have made observations of the potential gradient of the atmosphere in the industrial district around Leeds, and they find it is exceptionally large, a result attributable to the gases poured into the air from the numerous furnaces in the vicinity.
The relation of annual drainage yield to rainfall has been discussed by D. Halton Thomson, who shows that a rainfall, over say twenty years, of a given frequency produces a yield of the same frequency, and that a simple formula can be obtained connecting these quantities. Thus at Sheffield the yield is equal to the rainfall minus fourteen inches, the evaporation of fourteen inches being quite constant whatever the rainfall. This constancy of evaporation does not hold at all places, for at Torquay the evaporation varies to a small degree with the amount of the rainfall.
An unexpected and curious see-saw between the rainfall of Havana and of the South-West of England and South Wales has been discovered by Mr. A. H. Brown in the course of a study of Cuban rainfall. In Havana during May to October there is a wet season, and an excess of rainfall in this season is very generally associated with a deficient rainfall at the beginning of the next year in the parts of England mentioned; on the other hand a deficiency at Havana is the precursor of excess in the south-westerly parts of England and Wales.
A paper on "Canadian Weather Forecasting," by Mr. B. C. Webber, has been issued by the Meteorological Office of Canada. It covers the period 1874-1904 and supplies a quantity of statistical information on percentages of low pressure areas causing storms, the directions in which depressions move, etc. On the Great Lakes November is the stormiest month, but on the Gulf of St. Lawrence storms are most frequent in January and February. Since January, 1912, the Canadian Meteorological Office has issued a daily meteorological chart of the northern hemisphere, but the advance of forecasting has not been very rapid and further progress will probably not be made until more detailed information of the upper air, especially of the stratosphere, is obtainable, as it is now recognised that the character of the ground weather is much influenced by the condition of this layer of air.
Professor W. R. Blair observes that up to 1½ kilometres above the earth's surface the same type of daily variation of weather elements is found as at ground level, but above this height a second maximum appears after midnight, the time of which alters with increasing altitude.
An interesting paper in Himmel und Erde, by Professor G. Hellmann, deals with superstitions relating to weather, and under the head of character and causes of the weather he reminds us of the prevalence of the belief in equinoctial gales, although the evidence of careful observers is not in favour of stormy winds at the equinoxes. Sayings in relation to the colour of the sky in the morning and evening are not without some measure of truth in predicting the weather, but prognostications of the weather from the moon, although persistently found, have very little to support them when tested by reliable observations. Lastly, the making of weather, for example the firing of cannon to produce rain, or the warding off of thunder by the ringing of church bells, still in vogue in parts of Switzerland, is a superstition which dies hard, although completely discredited by science.
Dr. A. E. Douglass has published an account of his investigations on tree growth in relation to rainfall, and from an examination of the growth of rings in trees, involving 10,000 observations, he concludes that definite rainfall information in the past can be obtained from the mode of growth of trees. The average age of the trees examined was 348 years.
Upper air investigations are likely to suffer from the advent of the war. International days were fixed to the end of the year but not after, and meetings of International Committees will probably be suspended. The Manchester station has been closed since the beginning of the year and the station at Pyrton Hill ceased to be available in the spring, but its work is now being carried on at Benson six miles W.S.W. of Pyrton Hill.
In all parts of the British Isles the mean temperature of the year was in excess by as much as 2° in the East and North-East of England and the Midland counties, and by about 1° in other parts of the country. The high temperature of 90° in the shade was touched in the South of England and the lowest temperature of the year, namely 7°, occurred in the East of Scotland. The rainfall was greatest in the North of Scotland, where it reached 49.31 inches, and least in the North-East of England, the fall there being 24.82 inches; in most parts of England and in the south of Ireland the amount was decidedly above the average. Sunshine was normal.