Global rainfall anomalies in the 18th century

E. Linacre

11/'98


Very little is known about temperature and rainfall variations before the mid-19th century, when the daily recording by means of more accurate instruments became practice in most regions. Yet a notable growth of interest in climatology occurred as early as the 18th century (1). A friend of Isaac Newton, Junius Jurin, wrote a paper in 1724 calling for networks of weather stations around the world, which did lead to systematic daily measurements at St Petersburg, in Massachusetts, in Bengal, Canton, etc. Unfortunately these plans were interrupted by the subsequent wars in Europe. Following presentations and publications by Joseph Priestley (who discovered oxygen), the building of a global network of weather stations resumed in the 1770ís. This provided the first measurements on rainfall anomalies worldwide. Temperature data were too sparse and inaccurate to detect interannual trends. The 1791 drought was the first recorded and probably the worst within the period of written history. It is confirmed by records of low flows of the Nile, and by environmental evidence in north China, the East Indies, India, Peru and Australia, for instance.

Droughts occurred in southeast Australia in these years -

1789-91, 1793, 1797, 1798-1800, 1802-4, 1808-15, 1818-21, 1824, 1827-9, 1833, 1837-9, 1842-3, 1846-7, 1849-52, 1855, 1857-9, 1861-2, 1865-9, 1872, 1875-7, 1880-1, 1884-6.

In India they occurred in -

1790-2, 1802-4, 1812-3, 1824-5, 1828, 1832-3, 1837-9, 1856-8, 1865-6, 1875-7, 1884 (1).

It is interesting to note the coincidences. Unusually weak flows of the Nile were recorded in the following years -

650, 689, 694, 842, 903, 967, 1096, 1144, 1200, 1230, 1450, 1641, 1650, 1694, 1715, 1783, 1790-97, 1877, 1913, 1972 (3).

 

References

(1) Grove, R. 1998. The East India Company, the Raj and the El Niño. In Grove et al 1998, 301-23 (2).

(2) Grove, R., V. Damodaran and S. Sangwan (eds) 1998. Nature and the Orient (Oxford Univ Press) 1036pp.

(3) Quinn, W.H. 1992. A study of Southern Oscillation related climatic activity for AD 622-1990 incorporating Nile River flood data. In Diaz and Markgraf 1992, 119-50 (4).

(4) Diaz, H.F. & V. Markgraf (eds) 1992. El Niño; historical and paleoclimatic aspects. (Cambridge Univ Press) 476pp.