Historical climatology is an interdisciplinary field of research encompassing the reconstruction of past climate and weather from written sources and artifacts, as well the application of climate reconstructions to the study of human history. Historical climatology has grown in recent years, and this growth has brought both insights and challenges. Research has expanded into new regions and periods and diversified into novel sources, methods, and interdisciplinary collaborations. At the same time, the heterogeneity of evidence and approaches has complicated the integration of multiple climate and weather reconstructions. Moreover, the diversity of disciplinary perspectives, terminologies, and perspectives can create miscommunication among scholars in the field, particularly on issues of historical knowledge and causation. Innovative approaches in the field, including Bayesian methods, may help address these challenges.This article is categorized under: Climate, History, Society, Culture > Disciplinary Perspectives Climate, History, Society, Culture > World Historical Perspectives Assessing Impacts of Climate Change > Representing Uncertainty The Social Status of Climate Change Knowledge > Knowledge and Practice

The Czech Lands are particularly rich in documentary sources that help elucidate droughts in the pre-instrumental period (12th–18th centuries), together with descriptions of human responses to them. Although droughts appear less frequently before 1501, the documentary evidence has enabled the creation of a series of seasonal and summer half-year drought indices (Standardized Precipitation Index, SPI; Standardized Precipitation Evapotranspiration Index, SPEI; Z index) for the Czech Lands for the 1501–2017 period. Based on the calculation of return period for series of drought indices, extreme droughts were selected for inclusion herein if all three indices indicated a return period of ≥20 years. For further analysis, only those from the pre-instrumental period (before 1804) were used. The extreme droughts selected are characterized by significantly lower values of drought indices, higher temperatures and lower precipitation totals compared to other years. The sea-level pressure patterns typically associated with extreme droughts include significantly higher pressure over Europe and significantly lower pressure over parts of the Atlantic Ocean. Extreme droughts with a return period ≥ 50 years are described in detail on the basis of Czech documentary evidence. A number of selected extreme droughts are reflected in other central European reconstructions derived from documentary data or tree rings. Impacts on social life and responses to extreme droughts are summarized; analysis of fluctuations in grain prices with respect to drought receives particular attention. Finally, extreme droughts from the pre-instrumental and instrumental periods are discussed.

Extreme droughts are weather phenomena of considerable importance, involving significant environmental and societal impacts. While those that have occurred in the comparatively recent period of instrumental measurement are identified and dated on the basis of systematic, machine-standardized meteorological and hydrological observations, droughts that took place in the pre-instrumental period are usually described only through the medium of documentary evidence. The extreme drought of 1842 in Europe presents a case in which information from documentary data can be combined with systematic instrumental observations. Seasonal, gridded European precipitation totals are used herein to describe general DJF, MAM, and JJA precipitation patterns. Annual variations in monthly temperatures and precipitation at individual stations are expressed with respect to a 1961–1990 reference period, supplemented by calculation of selected drought indices (Standardized Precipitation Index, SPI; Standardized Precipitation Evapotranspiration Index, SPEI; and Palmer Z index). The mean circulation patterns during the driest months are elucidated by means of sea-level pressure (SLP) maps, the North Atlantic Oscillation Index (NAOI), and the Central European Zonal Index (CEZI). Generally drier patterns in 1842 prevailed in January–February and at various intensities between April and August. The driest patterns in 1842 occurred in a broad zonal belt extending from France to eastern central Europe. A range of documentary data is used to describe the peculiarities of agricultural, hydrological, and socio-economic droughts, with particular attention to environmental and societal impacts and human responses to them. Although overall grain yields were not very strongly influenced, a particularly bad hay harvest, no aftermath (hay from a second cut), and low potato yields led to severe problems, especially for those who raised cattle. Finally, the 1842 drought is discussed in terms of long-term drought variability, European tree-ring-based scPDSI (self-calibrated Palmer Drought Severity Index) reconstruction, and the broader context of societal impacts.

The eruption of Mount Tambora in Indonesia in 1815 was one of the most powerful of its kind in recorded history. This contribution addresses climatic responses to it, the post-eruption weather, and its impacts on human life in the Czech Lands. The climatic effects are evaluated in terms of air temperature and precipitation on the basis of long-term homogenised series from the Prague-Klementinum and Brno meteorological stations, and mean Czech series in the short term (1810–1820) and long term (1800–2010). This analysis is complemented by other climatic and environmental data derived from rich documentary evidence. Czech documentary sources make no direct mention of the Tambora eruption, neither do they relate any particular weather phenomena to it, but they record an extremely wet summer for 1815 and an extremely cold summer for 1816 (the "Year Without a Summer") that contributed to bad grain harvests and widespread grain price increases in 1817. Possible reasons for the cold summers in the first decade of the 19th century reflected in the contemporary press included comets, sunspot activity, long-term cooling and finally – as late as 1817 – earthquakes with volcanic eruptions.

This paper presents an analysis of fatalities attributable to weather conditions in the Czech Republic during the 2000–2019 period. The database of fatalities deployed contains information extracted from Právo, a leading daily newspaper, and Novinky.cz, its internet equivalent, supplemented by a number of other documentary sources. The analysis is performed for floods, windstorms, convective storms, rain, snow, glaze ice, frost, heat, and fog. For each of them, the associated fatalities are investigated in terms of annual frequencies, trends, annual variation, spatial distribution, cause, type, place, and time as well as the sex, age, and behaviour of casualties. There were 1164 weather-related fatalities during the 2000–2019 study period, exhibiting a statistically significant falling trend. Those attributable to frost (31 %) predominated, followed by glaze ice, rain, and snow. Fatalities were at their maximum in January and December and at their minimum in April and September. Fatalities arising out of vehicle accidents (48 %) predominated in terms of structure, followed by freezing or hypothermia (30 %). Most deaths occurred during the night. Adults (65 %) and males (72 %) accounted for the majority of fatalities, while indirect fatalities were more frequent than direct ones (55 % to 45 %). Hazardous behaviour accounted for 76 %. According to the database of the Czech Statistical Office, deaths caused by exposure to excessive natural cold are markedly predominant among five selected groups of weather-related fatalities, and their numbers exhibit a statistically significant rise during 2000–2019. Police yearbooks of the fatalities arising out of vehicle accidents indicate significantly decreasing trends in the frequency of inclement weather patterns associated with fatal accidents as well as a decrease in their percentage in annual numbers of fatalities. The discussion of results includes the problems of data uncertainty, comparison of different data sources, and the broader context.

Using documentary data and long-term temperature and precipitation series for the years 1775–2007, climatic, weather and other phenomena in the Czech Lands following the 1783 Lakagígar eruption in Iceland and the 1815 Tambora eruption in Indonesia are investigated. The Lakagígar eruption had clear post-volcanic effects on the weather in central Europe (dry fog, heavy thunderstorms, optical phenomena), with the occurrence of significant cold temperature anomalies in winter 1783/84, spring 1785 and the summer and autumn of 1786. The Tambora eruption was not accompanied by any particular weather phenomena, but was followed by an extremely cold summer in 1816. A comparison of the two eruptions shows that the effects of the Lakagígar eruption were climatologically stronger than those of the Tambora eruption.