In 1799 and 1800, crop failures struck the British Isles. The crop failure of 1799 was due to the combined effects of the cold winter of 1798–99 and the cool and rainy growing season of the year. The summer was characterized by the prevalence of low-pressure systems resembling cyclonic weather patterns of the winter.
The crop failure of 1800 was mainly due to a drought early in summer. In July there was either no rain at all (especially in the south) or the amounts were negligible. The general synoptic situation indicated an extension of the Azores High to Britain and beyond to central Europe. In the London area the pressure in July was never below 1020 mb.
The wheat harvests of 1799 and 1800 were about one-half and three-quarters of the average, respectively. The deficiencies could not be made up by imports, for, at least in 1799, the weather conditions were also unfavorable to grain production in the countries of northern Europe that were “traditional” exporters of grain to Britain. We estimate that in the “bread-consumption year,” October 1799 to September 1800, harvest and imports accounted for but 60% of the required quantity of wheat, the principal ingredient of bread in England and Wales at the time. In consequence of the bread scarcity, there were sharp rises in the price of bread and in bread riots. Some of the slogans of the rioters made mention of the French Revolution.
In parallel with the increasing scarcity of bread, diplomatic relations between Britain and Russia worsened from 1799 on. Its significance on the bread crisis, as well as a crisis of naval supplies, was that the Baltic ports through which the grain of the northern countries (East Prussia, Poland, and Russia) was channeled for Britain stood under the tsar's direct or indirect control. The strained relations between Britain and Russia peaked in November 1800. On 18 November, Tsar Paul I imposed an embargo on British ships and their crews. This embargo meant that the bread scarcity was to become even graver, even more threatening, in 1801. On 28 November (apparently), the British cabinet decided to launch a naval war against Russia in the Baltic as soon as ice conditions permitted. In Dudley Pope's (1972) words, “at this stage the climate governed Britain's naval strategy and planning for the Baltic.” When the decision of late November was taken, it was directed against Russia alone. Its primary purpose was to break the embargo. Subsequent complications involving the other northern powers (mainly Denmark and Sweden), led to an extension of the plan of a naval war to include all the northern powers.
+Part 9, “The Year Leading to the Revolution of 1789 in France (II),” was published in the January 1990 Bulletin (71, 33–41). See Part 9 for a complete list of the previous articles.
*Department of Atmospheric Sciences, The Hebrew University, Jerusalem, Israel; visiting with the Department of Meteorology, University of Copenhagen, Copenhagen, Denmark.
**Climatic Research Unit, University of East Anglia, Norwich, England.