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Physical Geography of Northern Eurasia
Climate at Present and in the Historical Past
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Period | Physical Geography Index | Climate
within the Period of Instrumental Meteorological Records >>>
Documentary Sources
An array of written documentary sources is available for Northern Eurasia. These can be
broadly split into three categories: irregular information, dating back to antiquity, for
the Crimea, Central Asia, and Transcaucasia; regular and irregular records, made prior to
the mid-16th century, available for parts of the East European plain and the Baltic
region; regular and irregular records made after the Russian advance to the trans-Volga
region and Siberia in the middle 16th century. So far, not all of these sources have been
researched. The most thorough studies of historical climates using written evidence are
those by Borisenkov and Pasetsky (1983, 1988) and Lyakhov (1984a, b, 1987). These works
provide a wealth of climatic information for the East European plain during the last
thousand years.
The major original source of meteorological information for the East European plain
between the 11th and the 17th centuries are chronicles which contain abundant information
about the weather and weather-related events. These were published as a 37-volume edition
The Complete Collection of the Russian Chronicles between 1841 and 1982 in Russian and
translated into the main European languages. Chronicles were kept by the monasteries and,
although the first written records mentioning anomalous weather date back to 867, regular
recording of political, social and natural events began at the end of the 10th century
after Christianity was adopted by the Slavs and the first monasteries were established. It
continued more or less uninterrupted until the Mongol invasion in the 13th century. As the
Mongols conquered Eastern Europe, such major religious centres as Ryazan, Vladimir,
Torzhok, Kiev, and Chernigov were ravaged and chronicle-keeping in this part of Russia
declined. However, it did not stop entirely as new centres emerged in the north: in
Galich, to which chronicle-keeping moved from Kiev, and in Rostov Veliky and later Tver,
which took over from Vladimir. The two major centres, Novgorod and Pskov, remained free.
These cities became the main centres of chronicle writing as well as two monasteries, the
Solovetsky and Kirillo-Belozersky, established under the influence of the Novgorod state
in the White Sea region. Later, in the 14th and 15th centuries as Christianity was
restored and the unified Russian state began developing around Moscow, the geography of
chronicle-keeping expanded, reaching the Volga region in the 16th century and, eventually,
Tobolsk and Irkutsk in Siberia before declining in the 17th century. The most complete and
extensive records are available, therefore, for the Novgorod and Pskov regions, followed
by central Russia and northern Ukraine (Borisenkov and Pasetsky, 1983; 1988; Lyakhov,
1995a).
The major issue in using historical documentary sources for climatic reconstruction is
that of source reliability. “The descriptions of natural phenomena in the chronicles”,
says Lyakhov (1995a) “can be considered as trustworthy because they are corroborated by
other factual information, about the scale and consequences of the event in the first
place. It should be also noted that nowhere in the chronicles is there a description of a
phenomenon which has not occurred during the period of established meteorological
observations. This points at the absence of exaggeration by the authors of the
chronicles”. Thus the so-called Troitsk chronicle, which documented life in the regions
of Rostov Veliky, Moscow, Tver, Ryazan, and Smolensk in the 13th and 14th centuries,
provides a description of the extremely dry summer of 1371, giving detailed information
about the failure of crops and widespread forest and peat fires. As Borisenkov and
Pasetsky (1983) point out, this description closely resembles the extreme drought of 1972
and its consequences. Usually, weather-related information given in a chronicle is
corroborated by a description of similar events in other contemporaneous chronicles. While
providing detailed descriptions of weather and often giving the exact date and time of the
events, most chronicles remained free of mystical comments about the nature and origin of
the described events. The Novgorod chronicles are especially known for their informative
and objective style.
Monastic chronicles declined in the 17th century. The main regular written sources of
meteorological and weather-related information for the period between the 17th and the
19th centuries are various types of governmental documentation. These encompass the whole
of the Russian state which extended from Poland and Finland in the west to the Pacific in
the east. Regular records and reports, which included weather and weather-related
information, were made not only in European Russia but also in the settled regions of
Siberia. Among the earliest of these documents are records kept by the Kremlin Guards in
Moscow under the order of Tsar Aleksey Mikhailovich. The records, which encompass the
period between 1657 and 1675, depict the weather with great precision, providing both
qualitative descriptions and exact timing. Lyakhov (1995a) gives an example of such a
record: “Year 7165 (1657 according to the modern calendar), 4 February, Wednesday. The
day was warm and windy; it started snowing half an hour before midnight and was snowing
until the fifth hour of the night and it was warm during the night”. In 1696, Peter the
Great issued an order to the Navy to keep weather records as a part of ship journals. The
records were made six times per day and included wind direction, descriptive
characteristics of wind speed (i.e., strong or stormy), cloudiness, descriptive
characteristics of temperature, precipitation and its nature, visibility, and weather
phenomena (i.e., fog or thunderstorms together with the exact timing of events). These
observations provide valuable information about the weather in the Baltic, White, and
Barents Seas, the Caspian and the Sea of Azov, and the Pacific Seas. A number of ships
were guard vessels and, remaining at the same position, served as 'weather vessels'. These
were numerous in the Baltic and in 1720 five guard vessels were dispatched in the Gulf of
Finland alone (Borisenkov and Pasetsky, 1983; Lyakhov, 1995a). In addition to the regular
weather documentation, there are numerous personal diaries and reports by expeditions
which actively explored the Arctic regions, Siberia, and the Pacific. Tax records,
manorial books, and records of crop prices provide another source of data. While manorial
records give phenological information and dates and conditions of harvests which can be
correlated with weather conditions, tax and price records are a more ambiguous source of
climatic data because they depend on political, social, and economic factors as well as on
quality and quantity of harvest. Likewise, poor harvests and famines are not always caused
by the unfavourable weather.
Weather information is abundant in the written historical documents but its utilization
is difficult. Although (and sometimes if) the observers and recorders of information were
truthful and objective by the standards of the time, their standards, however high, are
incompatible with the rigour of contemporary meteorological observations. Descriptions
rely on second-hand information and, with the exception of the more recent weather
diaries, it is the chronicle or diary-keeper who selects information. Data derived from
the written historical documents are, therefore, subjective in terms of both inclusivity
and observing standards. Weather phenomena were chronicled in greater detail during the
military campaigns or political events. Thus, the anomalously dry summer of 1060 and cold
winter of 1067 are described in the Kiev chronicles in the context of military actions. No
climatic extremes were registered between 1025 and 1058 although it is known that these
were frequent both in Western Europe and Byzantium (Borisenkov and Pasetsky, 1983). Was it
because of climatic stability on the East European plain or because records were more
sporadic during the peaceful time? Likewise, following numerous reports of extreme weather
in 1230, records of hazardous weather were few during the 1230s and 1240s (Borisenkov and
Pasetsky, 1983). This period is known as climatically stable in Western Europe but another
factor, the devastation of monasteries by the Mongols, could be a reason for the declining
number of reports in Russia. Not only did the contemporaneous observers have a different
perception of events, but their criteria could be and most likely were different from the
modern ones. Thus, while some information can be interpreted in unambiguous ways (e.g.,
freezing rivers imply subzero temperatures), reports of severe winters when people and
domestic stock were freezing to death are difficult to quantify as the perception of
severity might have changed or did change as well as quality of housing and clothes.
Undoubtedly, careful and cautious interpretation of historical documents is required.
Ideally, such interpretations should be integrated with information obtained from other
proxy sources.
There are three main approaches to the utilization of historical data. First,
short-term climatic anomalies, such as drought or floods, can be catalogued. Such
information is useful even when fragmented because it provides insight into variability of
extreme weather events. Climatic instability, expressed in the increasing frequency of
weather extremes, is seen as an indicator of changing climate and such information is
particularly useful in the context of the global warming debate. Second, the absolute
trends of climate change can be determined by categorizing time periods (usually decades
or 30-year periods) as warmer or colder and wetter or drier than the present climate.
Third, the established qualitative characteristics can be quantified as temperature and
precipitation time series. The first two tasks can be accomplished through the direct
examination of historical evidence. Thus catalogues of extreme weather events between the
11th and 19th centuries have been compiled by Borisenkov and Pasetsky (1983, 1988) for the
East European plain. These results are given in Figures 3.14 and 3.15.
Fig. 3.14 Anomalous weather in central European Russia and the northern
Ukraine between the 11th and the 15th centuries.
Compiled by M. Shahgedanova using data from Borisenkov and Pasetsky (1983)
Fig. 3.15 Running 20 year mean frequency of weather extremes and number
of years with poor crops.
Modified from Borisenkov and Pasetsky (1983)
Lyakhov (1984a, b; 1987) has produced seasonal chronologies in which each winter,
spring, summer, and autumn between the early 11th and the late 20th century is given a
qualitative characteristic. Quantification of historical information is the most
challenging task. Methodologies have been developed that make use of modern meteorological
data to reconstruct climatic characteristics of the past. For example, droughts or severe
frosts, reported in historical documents, can be interpreted in terms of weather types for
which modern average temperatures and precipitation totals are known. The frequency of
reconstructed weather types can be then used to determine approximate seasonal temperature
and precipitation. Another approach is to link frequency of the extremely cold (warm) and
wet (dry) seasons during a 30-year period with the 30-year temperature or precipitation
climatologies. Usually there is a close correlation between the means and the extremes
(Lyakhov, 1995a). In both methods, precipitation is more difficult to quantify than
temperature because of its strong spatial variability. The reliance on modern data
inevitably leads to the uncertainty in reconstructions as magnitudes of anomalies might
have changed. To enhance credibility of these reconstructions, other corroborative
information is used such as historical phenological or hydrological data. Using these
methods, Lyakhov (1995b) produced time series of temperature and precipitation extending
to the beginning of the 13th century.
Anomalously cold or warm seasons and mean temperatures for 30-year periods between 1201
and 1980 in Moscow and Kiev are given in Figure 3.16.
Fig. 3.16 Running 30 year means of temperatures in Moscow and Kiev
during the historical period.
Modified from Lyakhov (1995b)
Temperature chronologies are broadly consistent with those for Central and Western
Europe (Hughes and Diaz, 1994; Lamb, 1995). As elsewhere, mild winters and dry summers
were characteristic of the time which is known as the medieval climatic optimum. The 11th
century chronicles report relatively few severe winters and almost no May frosts. By
contrast, reports of droughts are frequent and the particularly devastating drought of
1060 is described in a document concerned exclusively with the drought and its
consequences. The heat and dryness of the summers were responsible for the plagues of
locusts which at times spread over vast areas, occasionally reaching as far north as
Novgorod. Another social and economic consequence of droughts was frequent fires which
devastated major cities. Reports of climatic extremes, became more frequent in the 12th
century, indicating the end of the most clement period of the medieval climatic optimum.
In addition to previously reported droughts, there are records of late spring and late
summer frosts, storms, and floods. Thus, in 1143 and 1145, wet weather that lasted from
August to December caused extensive famine in Novgorod. For the first time ever,
chronicles report frosts and snowfalls in June. Characteristic of the 12th century, is the
alternation of extremely severe and extremely warm winters. This instability continued
into the early 13th century which Borisenkov and Pasetsky (1983, 1988) describe as one of
the most climatically unstable periods in history. During the first third of the century,
there were seventeen years of famine caused by climatic hazards including famines which
lasted for a few consecutive years such as in 1214-16 and 1230-3. These famines affected
the north-east (i.e., Vladimir and Suzdal) particularly badly, leading to grave social
effects and dramatic population decrease. However, the subsequent forty years were notably
quiescent. Although chronicle-keeping declined during this period, the continuing
chronicles reported solar and moon eclipses and northern lights but not hazardous weather.
The last two decades of the 13th century marked the onset of yet another climatically
unstable period which continued throughout the 14th century. The record number of droughts
was observed and these alternated with equally damaging cold and wet summers (Figure
3.15).
However, despite the increasing instability, the climate remained mild and not until
the end of the 14th century did severe winters and cold autumns and springs become
prominent. Lyakhov (1995b) estimated that in the 13th and 14th centuries, winter
temperatures were just below the current norm while in the following centuries winter
temperatures were 2-3 °C below the current norm. While Vikings established settlements in
Greenland and Iceland, the Slavs settled the Arctic coast, reaching as far north-east as
Novaya Zemlya, the existence of which was first reported in the 13th century. The
deterioration of climate, known as the Little Ice Age, began at the end of the 14th
century and continued until the end of the 19th century (Grove, 1988; Bradley and Jones,
1992). Although climate declined across the Eastern European plain, the biggest change
initially occurred north of Moscow. The climatic reverse involved both, severe winters and
cold and wet summers alternating with droughts and it is this instability that affected
the economy more than the increasing severity of the winters. In the 15th century,
famines, caused primarily by wet and cold summers, occurred for forty years in the Moscow,
Novgorod, and Pskov regions. However, it was the winter temperatures that displayed the
greatest anomalies (Figure 3.16). The severity of winters manifested itself through the
changing ice conditions in the Baltic, in the northern seas and even the Black Sea.
Koslowski and Glazer (1995, 1999) reconstructed sea ice conditions in the Baltic between
1501 and 1995 and showed that both extent and duration of sea ice between the 1550s and
the 1860s were considerably higher than now. By contrast, the growth of sea ice in the
Arctic was delayed until the second half of the 17th century and while western and central
parts of European Russia experienced extremely unstable and increasingly severe climate,
weather in the north was comparatively mild. However, in the 17th century the climate in
Eurasia became almost universally cold, affecting the Arctic Seas, all of the East
European plain, Crimea, and Transcaucasia and it was not until the second half of the 19th
century that amelioration of climate occurred (Borisenkov, 1992). Discussion of the
regional aspects of climate change in the subsequent chapters of this volume confirms the
continental scale of the Little Ice Age. However, few cold or warm decades appear to have
been synchronous. Documentary evidence became plentiful in the 16th century encompassing
not only the East European plain but also Siberia and the Far East. Much of these sources
have not been researched.
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