the houses - wood, brick, or any kind down like ninepins. The damage is estimated at some f80,000,000 and it will be some two months before a lot of the *arks will be functioning again. At least 1 600 people were killed ashore, and many thousands injured, and some 2500 fishing boats are known to have been lost, with an unknown loss of life. The countryside for miles around looks as if an earthquake had struck it - splintered trees, fallen houses and temples etc. They say it is the worst typhoon Japan has ever suffered: I can believe it is.

The trouble seems to have been that, although they knew a typhoon was coming, they were caught unprepared for it, as it was travelling exceptionally fast, some 700 miles a day . . .”

In a covering letter Rear Admiral Donaldson writes: “Immediately after the typhoon passed reports came in of an eruption of a

submarine volcano out the northern end of the Liu-chu chain of islands to the south of Japan. After leaving Japan, we made a slight detour to sight the eruption, which was taking place in the narrow strait between two small islands. We were able to pass, through a sea covered with pumice, within about one and a half miles of the eruption. A plume of vapour rose over it to a height of about 6000 feet (as measured on our height finder) and occasionally large rocks could be seen being thrown up out of the water to almost the top of the plume of water vapourlsteam etc. . . . It was suggested to us before we sailed from Kobe that the passage of the typhoon . . . with its dramatic pressure variation, could have been the trigger which set off the eruption. I have no idea whether there is any possibility of this suggestion having any validity.” The Editor would welcome comments from readers on the possibility of links between volcanic eruptions and surface pressure variations.

HOT SUMMERS IN CENTRAL ENGLAND AND CENTRAL ENGLAND TEMPERATURE

In his recent letter to Weather, Beresford (1984) highlighted inconsistencies between values of Central England Temperature (CET) quoted by different authors when discussing recent hot summers in the UK (notably 1975, 1976 and 1983). The problems arise mainly from different selections of meterological observing stations and the completeness of the quality control of the data quoted at any particular time. A data set of daily CET has recently been completed in the Synoptic Climatology Branch of the Meteorological Office and Manley’s (1974) monthly series has been brought up to date. An important aim of the project was the completion of a homogeneous record of daily mean CET consistent with the published monthly mean data set, so that the mean of the daily values in any month is equal to the monthly mean published by Manley. The daily data is updated regularly and has been homogenised satisfactorily from 1878 to date, and moderately well from 1772 to 1877. The details of the project will appear elsewhere, but it is thought useful to provide some authoritative statistics similar to those in Beresford’s letter.

Figs. l a to lc shows for each day the daily mean CET for the three summer months (June, July and August) in the three most recent hot summers (1975, 1976, 1983). They show well how the choice of a shorter period to highlight an outstanding summer can affect the perception of how warm that summer was. In an effort to illustrate this problem Table 1 was constructed to show the warmest periods of varying lengths and definition during the summer months. Values for calendar months were taken from

287

10-

"C 25-

20-

15-

10-

288

1983

1 I 1

Manley's monthly series (which started in 1659), while values for all other periods were calculated from the homogenised daily series which starts in 1772.

The 3O-day and 61day warmest periods have all occurred during recent years. This perhaps gives the impression that only recent years have been warm, but can be explained by the large autocorrelation that exists between daily mean temperature values; note that many of the periods overlap considerably. The first appearance of warm periods in years other than 1983, 1976 and 191 1 which would feature in an extended Table 1 would be the 3May periods beginning 9 July 1868 and 26 July 1947 which lie joint 29th in the 3O-day ranking (19.1 "C), and the 61-day period beginning 2 July 1955 which lies joint 28th in the 61-day ranking (17.9OC).

1976 19.8 1976 19.7 1976 19.7 1911 19.6 1976 19.5 1976 19-5 191 1 19.5

191 1 19-5

191 1 19.5

1983 19.5

191 1 19.5

Meteorological Office, Brac knell

2 July-31 August 1983 18.3 25 June-24 August 1976 18.3 26 June-25 August 1976 18.3 24 June-23 August 1976 18.3 23 June-22 August 1976 18.3 22 June-21 August 1976 18.3 27 June-26 August 1976 18.3

28 June-27 August 1976 18.2

21 June-20August 1976 18.2

2 July-31 August 1911 18.3

2 July-31 August 1976 18.2

A" STOREY C. K. FOLLAND

19.3 18.8

July 1983 July 1783 Julv 1976. Julv 1852 18.7

REFERENCES Beresford. A.K. (1984) Hot summers. Weather, 39(6), pp.193-195 Manley. G. (1974) Central England Temperatures: monthly means 1659 to 1973. Quart. J . Roy.

Met. Soc, 100, pp. 389-405

July/August 1983 18.3 June/Jufy/August: July/August 1911 18.2 1976 17.7 I 17.6 Julv/Aunust 1976 18.1 1826

TABLE 1. Warmest 3May and 61day summer periods 1772-1983, and warmest one, two and three calendar-month summer periods 1659-1983. ('Summer'- June, Jufy und August)

August 15675. August 1947 18.6

WARMEST 30-DAY PERIODS I WARMEST 61-DAY PERIODS

Ju&/Auiust 1975 18.0 1846 17.1 July/August 1955 17.9 1983, 1947, 1933,

1911, 1781 17.0 1899, 1975. 1868 16.9

30-day period Year M e a n T I 61dayperiod Year Mean'C 22 June-21 July 21 June-20 July 23 June-22 July

20 June-19 July 24 June-23 July

21 July -19 August

22 July-20 August 3 July-1 August

18 July-16 August 19 July-17 August 20 July-18 August

WARMEST ONE CALENDAR WARMEST TWO CALENDAR WARMEST THREE CALENDAR MONTH PERIODS I MONTHPERIODS I MONTHPERIODS

Month ~ e a n oc I Period ~ e a n "C I Period Mean "C

ROYAL METEOROLOGICAL SOCIETY

MOUNTAIN WEATHER

Copies of this guide are available from James Glaisher House at f3.30 to non- members and f2.80 Members (including p&p), not at the prices advertised in the June issue of Weather.

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