Pressure reductions at high‐level stations

Mr. Alan Smith's letter on ``Lack of uniformity in climatological pressure fields?'' (Weather, 1997, 52, pp. 362-363) raises some points which may be of interest to people who have never had occasion to think about the complexities inherent in pressure reductions to sea-level. May I, as one concerned with such problems for many years, offer some comments? So begins this brief review of problems associated with climatological pressure fields. Practices for dealing with these problems are offered.