Regional Studies Based On Historical Records

The large number of studies in East Asia and Europe enable a regional synthesis of paleoclimatic conditions to be made from historical data. Elsewhere, either there are insufficient documentary sources (e.g., in Africa or Australia) or detailed studies have yet to be carried out. One neglected resource is the vast archive of marine records, which contain valuable information about wind direction, wind speed, cloud cover, water temperature, and other parameters (Frich and Fryendahl, 1994). At higher latitudes, such records can provide much information about the sea-ice conditions that greatly affected sailing conditions in northern waters (Catchpole, 1992).

II .3.1 East Asia

Dynastic records, local histories, and diaries from China, Korea, and Japan are valuable sources of information about past weather events and their impacts on these largely agricultural societies (Table 11.6). Numerous investigators have sifted through these archives to extract weather-related information (see, for example, the volumes edited by Zhang, 1988 and Mikami, 1992a).

In China, most studies have been carried out on records from the lower Yangtze River basin and regions to the north (R. Wang and S. Wang, 1989; S. Wang, 1991a, b; S. Wang and R. Wang, 1990). A few studies have developed methods that use observations of extreme or intermittent events to estimate monthly or seasonal temperature or rainfall anomalies (R. Wang et al., 1991). This may involve calibrating the data with instrumentally recorded temperatures at representative sites, such as Beijing or Shanghai (W.C. Wang et al., 1992). More often this key procedure is poorly documented, making it difficult to judge how reliable the reconstructions really are. There is a need for much more work on rigorously calibrating these valuable records; bearing this caveat in mind, the following conclusions can be derived from the published literature. The coldest periods in the last 600 yr (or those with the highest frequency of unusually cold events) were in the mid- to late-seventeenth century and in the early to mid-nineteenth century (Fig. 11.11). The 1650s were exceptionally cold throughout eastern China and Korea (Kim, 1984, 1987). Indeed, Kim and Choi (1987) believe that summers in the period 1631-1740 were the coldest of the past 1000 yr. During this interval, snow occasionally fell in southern China and there were even killing frosts that severely damaged vegetation as far south as 20° N (Li, 1992). Temperatures increased during the eighteenth century, reaching levels comparable with the early twentieth century for brief periods in some regions. Cool conditions were again common in the early to mid-nineteenth century, but warmer conditions set in abruptly at the start of the twentieth century, with temperatures reaching the highest level of the last 500 yr in the period 1920-1940 with cooling thereafter. During both of the cold periods, in the seventeenth and nineteenth centuries, the frequency of floods and droughts increased, pointing to greater instability in climate during those times (Zheng and Feng, 1986).

In Japan, many documents dating from the Edo era (late seventeenth to early nineteenth century) contain records of daily weather conditions (Fig. 11.12). This has enabled monthly climatological maps to be constructed for 1700-1870, using daily

TABLE 11.6 Paleodimate Series Constructed for East Asia Based on Historical Records

Region

Sp

Su

Fa

Wi Ann

Record of:

Interval

Ref. period

Period

Source

1 East China

X

x

X

X

X

Temperature anomalies

10

1470-1980

1470-1980

Wang S. and Wang (1990, 1991) Wang S. (1991b)

2 North China

X

X

X

X

X

Temperature anomalies

10

1470-1980

1470-1980

Wang S. and Wang, R. (1990, 1991) Wang (1991a)

3 South China (5 regions")

X

Temperature anomalies

10

1470s-1970s

Zhang (1980) Zhang (ed.) (1988)

4 China

X

Number of cold winters

10

1500s-1970s

Zhang and Gong (1979)

5 Lower Yellow River

X

Number of frosts

10

1440s-1940s

Zhang and Gong (1979)

6 Shandong province

X

Cold winter index

10

1500s-1970s

Zheng and Zheng (1992)

7 Southeast China (Shanghai)

X

X

X

X

X

Temperature anomalies

10

1950-1979

1470s-1970s

Wang et al. (1991)

8 Mid and South China (S. of 35°N)

X

Temperature anomalies

10

1951-1980

1470s-1970s

Wang and Wang (1989)

9 China

X

Thunder events

30

190 BC-1920

Wang (1980)

10 Middle and Lower Yangtse

X

Temperature indices

10

1470s-1970s

Zheng and Feng (1986)

11 Eastern China

X

"Dust Rain" events

1

<300 BC-1933

Zhang (1983)

12 Beijing

X

X

Mean temperatures

1

1724-1986

Wang et al. (1992)

13 S. China

X

Frost, snow (irregular)

1

1488-1900

Li (1992)

14 China

X

Winter monsoon index

10

1390-1980

Guo (1992)

15 Korea

X

Number of cold events

50

1392-1900

Kim(1984)

16 Hirosaki, Japan

X

X

X

X

X

Maximum temperature

20-40

1661-1870

1661-1870

Maejima and Tagami (1983)

17 Japan

X

X

Temperature index

10

601-1900

Maejima and Tagami (1986)

18 Japan

X

Temperature

1

1950-1970

1771-1840

Mikami (1992)

19 C.Japan

X

X

Temperature, precipitation

1

1801-1870

Mizukoshi (1992)

20 C. and S. Japan

X

X

Snow/rain ratio; summer rainfall

1

1670-1860

Tagami and Fukaishi (1992)

21 C. and S. Japan

X

Synoptic type frequency

1

1720-1869

Fukaishi and Tagami (1992)

"Region I: Eastern part of Changjiang River Basin; Region II: Central part of Changjiang River Basin; Region III: Hunan and Jangxi Provinces; Region IV: Southeastern Provinces; and Region V: Guangdong and Guangxi Provinces.

"Region I: Eastern part of Changjiang River Basin; Region II: Central part of Changjiang River Basin; Region III: Hunan and Jangxi Provinces; Region IV: Southeastern Provinces; and Region V: Guangdong and Guangxi Provinces.

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