How to cite: García-Pereira, F., González-Rouco, J. F., Melo-Aguilar, C., Steinert, N. J., de Vrese, P., Jungclaus, J., Lorenz, S., Hagemann, S., García-Bustamante, E., and Roldán-Gómez, P. J.: Land heat uptake: from Last Millenium proxy and model simulations to observational and CMIP6 products, EMS Annual Meeting 2023, Bratislava, Slovakia, 4–8 Sep 2023, EMS2023-584, https://doi.org/10.5194/ems2023-584, 2023.

Coastal upwelling is a process in which sea water from intermediate depths emerges along the west coast of continents in response to the intensity of the alongshore component of the wind. These areas are economically relevant as upwelled water is rich in nutrients, creating regions of great interest for fisheries.
Quantifying upwelling intensity at multidecadal to secular time scales is quite difficult. Upwelling is typically evaluated with indices based on sea surface temperatures, a variable that at the spatial scale required, inevitably makes use of satellite retrievals. Evidently, indices based on this method are limited to the satellite era. An alternative approach makes use of the ultimate driver of the upwelling: the wind velocity. This is typically done by using reanalysis products, a kind of data that in open ocean, strongly relies on wind observations taken from the International Comprehensive Ocean-Atmosphere Data Set (ICOADS) database. However, during the last decade, it has been suggested that at multidecadal scale, due to the changes in the observations methods, ICOADS’ velocities over the oceans could be biased toward increasing values, resulting in unrealistic trends in any wind-derived climate index.
In this work we bypassed these problems disregarding the wind velocity field and making exclusively use of in-situ wind direction observations to compute a so-called “Directional Upwelling Index” (DUI). This kind of “directional” indices can be tuned to measure the persistence of the alongshore winds at the coast and therefore, they are directly related to the presence of upwelling favourable conditions. As the wind direction observation was routinely taken by sailing ships traveling between Europe and Asia circumnavigating Africa since long ago, our DUI can be used to track the history of the upwelling in parts of the African coasts since the first half of the 19^th century, avoiding any problem related to possible biases on the wind velocity. This is a period much longer than that covered for traditional upwelling indices.
We have computed DUIs for several areas along the west African coast. In general, we have not found consistent long-term trends, although the results are dependent on the specific area analysed. At the Senegal-Mauritania latitude, the upwelling intensity has been very variable during the last two centuries and there is strong evidence of a large shift in the upwelling intensity that occurred around 1900. Further north, at the Canaries latitude, we found that the Atlantic Multidecadal Variability mode seems to control a significant part of the upwelling variability at decadal scales, resulting in an alternating change in the sign of upwelling trends computed over short periods. This could explain the contradictory results currently found in the bibliography at the time of interpreting the upwelling trends based on short series. 

How to cite: Gallego, D., García-Herrera, R., Mohino, E., Losada, T., and Rodríguez-Fonseca, B.: A documentary proxy for coastal upwelling, EMS Annual Meeting 2023, Bratislava, Slovakia, 4–8 Sep 2023, EMS2023-76, https://doi.org/10.5194/ems2023-76, 2023.

The climate of the Last Millennium (LM) was characterised in many regions by long periods of warmer and cooler conditions, like the Medieval Climate Anomaly (MCA; ca. 950-1250 CE) and the Little Ice Age (LIA; ca. 1450-1850 CE). These changes in temperatures can be linked to changes in the Earth’s energy balance, being the solar and volcanic activity the main drivers during the pre-industrial period. Even if the MCA and LIA are typically defined in terms of temperatures, reconstructions of the hydroclimate conditions from regions of North America, Europe, Northern and Central Africa, Northern and Central South America, and Central and Eastern Asia also show relevant changes during these periods, suggesting a large-scale impact on the hydroclimate.

To analyse these large-scale changes in the hydroclimate, and whether similar changes also extend to other periods of the LM outside the MCA and the LIA, an exhaustive compilation of all the available reconstruction-based and model-based sources providing information about the hydroclimate of the LM has been considered, including the Drought Atlases for Europe (OWDA), North America (NADA), Asia (MADA), and Mexico (MXDA), the Paleo Hydrodynamics Data Assimilation product (PHYDA), the Last Millennium Reanalysis (LMR), and model simulations from the Community Earth System Model - Last Millennium Ensemble (CESM-LME) and the Coupled Model Intercomparison Project Phase 5 (CMIP5) and 6 (CMIP6).

This analysis has shown large-scale changes in the hydroclimate of the LM, particularly relevant in tropical areas around the Intertropical Convergence Zone (ITCZ), in the area of influence of the Northern (NAM) and Southern Annular Modes (SAM), and in the Indian Monsoon region, extending from the Middle East to Southeast Asia. The use of several reconstruction-based products allowed the identification with a robustness assessment of those regions more impacted by hydroclimatic changes, while the comparison between reconstruction-based products and model simulations from different ensembles allowed an assessment of the contributions of external forcing and internal variability on the hydroclimate of each region.

How to cite: Roldán-Gómez, P. J., González-Rouco, J. F., Smerdon, J., and García-Pereira, F.: Large-scale changes in the hydroclimate of the Last Millennium from reconstructions and simulations, EMS Annual Meeting 2023, Bratislava, Slovakia, 4–8 Sep 2023, EMS2023-574, https://doi.org/10.5194/ems2023-574, 2023.

During the Qing Dynasty (1644–1911AD), there were more migrants toward southern coastal China, which contributed to the enough records for empirical analysis. In the meantime, the Qing period of China overlapped with Little Ice Age (LIA, 1400–1900AD), a period of abnormal climate with prolonged cooling and persistent hydroclimatic anomalies. Therefore, under this climatic background, the work to reconstruct the typhoon in southern coastal China will help to understand the linkage between natural disasters and abnormal climatic conditions, which has been insufficiently examined so far. 

To reconstruct the typhoon along the southern coastal regions in Qing China, both narrative and quantitative methods will be used. Based on the content of records, the typhoon occurrence will be identified. Furthermore, the consequence of typhoon event will be used to identify the strength of typhoon. Then, the occurrence and strength of past typhoon will be digitized and reconstructed based on the historical records. According to the digitized information, statistical methods and Geographic Information System (GIS) will enable spatiotemporal analysis on those numerical datasets.  

I will finally discuss the possibility to adopt a digitization approach for typhoon reconstruction. Current methods usually make use of natural archives/proxies and thus cannot fully consider the special features of archives of societies, although environmental studies should be guided by humanities. Therefore, I would like to develop some new digitization methods, such as text recognition methods to digitize the descriptive content of historical records into numerical data. It is thus a promising and innovative attempt to adopt a Machine Learning approach to recognize, digitize, and quantify the historical records, including the occurrence, duration, and severity of typhoon. 

How to cite: Pei, Q.: Digitization and reconstruction of typhoon along the southern coastal regions in Qing China, EMS Annual Meeting 2023, Bratislava, Slovakia, 4–8 Sep 2023, EMS2023-586, https://doi.org/10.5194/ems2023-586, 2023.

In Japan, diaries that record daily weather conditions since the 18th century have been kept in various parts of the country. The winter weather distribution in the Japanese archipelago is characterized by a north-south extension of the mountain ranges, with the Sea of Japan side having more snow days and the Pacific side having more sunny days. On the other hand, when temperatures are higher in winter, precipitation is more likely to be rain, and when temperatures are lower, it is more likely to be snow. Therefore, by obtaining a linear regression equation based on the correlation between the ratio of the number of snowfall days to the total number of precipitation days in winter and the average temperature for the period when meteorological observation records are available (since 1879), it is possible to reconstruct long-term temperature variations from the snowfall ratio obtained from diary weather records in historical periods. Based on this principle, we attempted to reconstruct winter temperatures in Nagasaki since 1700. Fortunately, Nagasaki has records of early meteorological observations by Dutch medical doctors from 1840 to 1860, before the start of official meteorological observations, which can be used to verify the reconstructed temperatures. The results show that winter temperatures in Nagasaki tended to be lower in the period from about 1700 to 1840, but warmed temporarily in the 1850s and 1860s, and then remained lower again until about 1950. The temperature reconstructions for 1840-1860, when the reconstructed and observed temperatures overlap, are almost coincident, demonstrating that the winter temperature reconstructions based on snowfall ratios are mostly accurate.

How to cite: Mikami, T.: An attempt to reconstruct winter temperatures over the past 300 years from snowfall ratios based on diary weather records, EMS Annual Meeting 2023, Bratislava, Slovakia, 4–8 Sep 2023, EMS2023-182, https://doi.org/10.5194/ems2023-182, 2023.

The impact of climate change on human society has been a significant issue in historical studies and is also vital for future adaptation to climate change. To understand climate change before the start of meteorological observations and its devastating impact on societies in the past, the spatial patterns of climate variations must be reconstructed with a higher temporal resolution than those provided by the annual data. Japan has a large volume of records, including those related to daily weather conditions from the 17th to 19th centuries, which can help with this reconstruction.

This study applied the method previously developed by Ichino et al. (2001) for estimating solar radiation from the weather records of the Japan Meteorological Agency (JMA) to those collected from historical diaries. Adjusting the classification of descriptions from historical diaries, which are recorded in various expressions, allowed for their application in the method constructed from the current JMA weather descriptions. We estimated solar radiation for 1720–1912 in Japan based on the weather descriptions recorded in historical diaries from Tokyo, pertaining to the Little Ice Age. We validated the estimation compared to solar radiation estimated from the JMA-observed sunshine duration. The reconstruction was combined with the estimation from sunshine duration and the observed solar radiation to create the solar radiation time series data for 1720–2022.

The method used in this study successfully reconstructed solar radiation data in an adequate manner for all seasons with a higher temporal resolution, compared to other methods, including the use of proxy data for assessing historical climate variation. In addition, solar radiation is a fundamental factor for not only the energy balance of the Earth but also the hydrological cycle and agricultural productivity. Therefore, this extended reconstruction of time series data could contribute towards discussing climate change and its effects on historical societies. Herein, we discuss the long-term variations of the reconstructed solar radiation data since the 18th century, focusing on its particular effects on famine.

Reference

Ichino M, Sakamoto N, Masuda K, Mikami T (2001) The method for estimating global solar radiation based on weather records－toward the climatic reconstruction in the historical period－. Tenki 48:823–830. (in Japanese)

Keywords

Solar radiation, Historical weather descriptions, Historical diaries, Little Ice Age, Climate change, Japan

How to cite: Ichino, M., Masuda, K., and Mikami, T.: Reconstruction of solar radiation in Tokyo since 1720 based on daily weather records in historical documents, EMS Annual Meeting 2023, Bratislava, Slovakia, 4–8 Sep 2023, EMS2023-177, https://doi.org/10.5194/ems2023-177, 2023.

To determine the climate conditions of SW Greenland in the second half of the 18th century, two series of meteorological observations have been used. The first series (Neu-Herrnhut, 1st Sep 1767−22nd Jul 1768) is the oldest long-term series of instrumental measurements of air temperature and atmospheric pressure made by Christopher Brasen (1738−1774). The second (Godthab, Sep 1784−Jun 1792) contains the most significant and reliable data for Greenland for the study period. Observations were made by Danish Reverend Andreas Ginges (1754–1812) using methodology and instruments provided by the Meteorological Society of the Palatinate. Sub-daily or daily data exist for the following periods: Sep 1784−Jun 1785, Jan−Jun 1787, Nov−Dec 1788, Jan 1790−Jun 1792 and are available in the manuscript entitled Astronomiske og meteorologisk Iagttagelser, anstillede i Godthaab i Grønland 1782–1792 and in the society’s yearbook Ephemerides Societatis Meteorologicae Palatinae, which contains data for 1787. All available historical data were quality controlled and corrected prior to being used to calculate daily (MDAT), monthly, seasonal and yearly means. Daily means have been used to calculate less typical climate statistics such as day-to-day temperature variability, thermal seasons, growing degree days (GDD), air thawing index (ATI), positive degree-days (PDD) and air freezing index degree-days (AFI).

            Compared to present day (1991–2020), air temperature in Godthab was, on average, warmer in 1767–68 and colder in 1784–92. In 1767–68, the turn of December to January was exceptionally warm, with positive MDAT reaching even 5 °C. So too was summer significantly warmer than today. On the other hand, in 1784–92, autumn and particularly winter were markedly colder than today, while temperatures in the rest of the year were comparable to present day. The GDD and ATI in each month in the expedition year 1767–68 were equal to or higher than the norm observed in 1991–2020. No important changes were observed for PDD, while AFI was usually lower than the present-day norm. The GDD and ATI in the period 1784–92 usually (except 1787) do not exceed the maximum and minimum values from 1991–2020. The PDD during the cold season (from October to April) in the period 1784–92 is close to the average and minimum PDD in 1991–2020, but the AFI values in 1784–92 are between the average and maximum AFI values calculated for 1991–2020.

The work was supported by the National Science Centre, Poland project No. 2020/39/B/ST10/00653.

How to cite: Singh, G., Przybylak, R., Wyszyński, P., Araźny, A., and Chmist, K.: Climate conditions in SW Greenland in the second half of the 18th century, EMS Annual Meeting 2023, Bratislava, Slovakia, 4–8 Sep 2023, EMS2023-79, https://doi.org/10.5194/ems2023-79, 2023.

The bioclimate in SW Greenland was estimated using two existing series of meteorological observations from stations located in this area: Neu-Hernhut (1^st Sep 1767 – 22^nd Jul 1768) and Godthab (Jan 1790 – Jun 1792). The first series is the oldest available long-term series of instrumental measurements for this region. Observations of air temperature, atmospheric pressure, and wind direction and force were made twice a day by Christopher Brasen (1738–74) at 8 a.m. and 2 p.m. The second series of measurements covers the period Jan 1784 – Jul 1792, but the lack of bioclimatic utility of the data (the frequent absence of the required wind speed data) limited its use to only the aforementioned 2.5 years. Observations were carried out in accordance with the instructions used by members of the Meteorological Society of the Palatinate, which also provided the necessary tools. Measurements were taken three times a day by the Danish Reverend Andreas Ginges (1754–1812), at 7 a.m., 2 p.m. and 9 p.m. These were included in a manuscript titled Astronomiske og meteorologisk Iagttagelser, anstillede i Godthaab i Grønland 1782–1792 (Det Kgl. Bibliotek in Copenhagen).

In order to present the bioclimatic conditions in this part of Greenland, the following indices and indicators were used: Wind Chill Temperature (WCT), Insulation Predicted (Iclp), and day-to-day changes in air temperature and atmospheric pressure. The obtained results were compared with contemporary conditions (1991–2020).

Wind Chill Temperature values in the 1789–92 expedition years were lower than at present. In the period January–June of the 1767–68 expedition, the threat to human health was less than at present (by 1.7 °C). For a man in motion (metabolism = 135 Wm^-2) the meteorological conditions of SW Greenland show that the required clothing insulation in 1791–92 (Jan–Jun) was similar to the modern period. During 1789–92, an increase of 0.1 clo in the clothing insulation required to obtain thermal comfort was recorded, while in 1767–68, there was a decrease (of 0.2 clo) relative to the period 1991–2020. Day-to-day variation in atmospheric pressure in the category of strong (8–12 hPa) and very strong stimuli (>12 hPa) most often occurred in the winter and spring months. Under this criterion, the expeditions of 1767–68 and 1789–90 were felt more strongly than in the modern period. During the four historical expeditions in the 18^th century, there was found, among other things, a slight increase (1–5%) in frequency of occurrence of significant (4–6 °C) and severe stimuli (> 6 °C) according to the day-to-day variation of average diurnal air temperature, as compared against the contemporary period.

The work was supported by the National Science Centre, Poland project No. 2020/39/B/ST10/00653.

How to cite: Chmist, K., Araźny, A., Przybylak, R., Wyszyński, P., and Singh, G.: Bioclimate conditions in SW Greenland in the second half of the 18th century, EMS Annual Meeting 2023, Bratislava, Slovakia, 4–8 Sep 2023, EMS2023-135, https://doi.org/10.5194/ems2023-135, 2023.

Knowledge about the climate before AD 1500 (e.g. for the medieval period) is very limited for many areas of the world, including central Europe. The paper presents the latest state of knowledge on the climate of Poland (Central Europe) in the period 1001–1500. This is achieved using: i) quantitative climate reconstructions published in the past two decades, ii) three new reconstructions exploiting dendrochronological data, iii) one reconstruction based exploiting an updated and augmented database of historical source data on weather conditions. The annual growths of coniferous trees in lowland and upland Poland is highly dependent on the temperature at the end of winter and the beginning of spring, especially February and March. All available reconstructions based on dendrochronological data represent mainly this time of the year. A limited number of reconstructions exist for summer. They are based on biological proxies and documentary evidence, the latter being limited to the 15th century only. In Poland, annual mean temperature correlates with winter temperature more closely than with summer temperature. Winter temperatures can thus be used as annual proxies. The Medieval Warm Period (MWP; also called the Medieval Climate Anomaly) is estimated to have occurred in Poland from the late 12th century to the first half of either the 14th or 15th century. Analysis of all available quantitative reconstructions suggest that the MWP in Poland was comparable to or warmer than the current temperature (1951–2000). The first half of the 11th century (both winter and summer) and the second half of the 15th century (only winter) were the coldest periods in the Middle Ages. Very limited knowledge exists about the wetness of the seasons in Poland. Information is available only from documentary evidence and mainly for the 15th century. Weather notes describing precipitation conditions are most plentiful for summer and then for winter. A very limited number exists for the transitional seasons.

            The greatest climate continentality occurred in the 15th century. Good agreement was found between the reconstructions of Poland’s climate and many reconstructions available for the area of Europe.

The work was supported by the National Science Centre, Poland project No. 2020/37/B/ST10/00710.

How to cite: Przybylak, R., Oliński, P., Koprowski, M., Szychowska-Krąpiec, E., Krąpiec, M., and Puchałka, R.: Poland’s climate in the medieval period, EMS Annual Meeting 2023, Bratislava, Slovakia, 4–8 Sep 2023, EMS2023-67, https://doi.org/10.5194/ems2023-67, 2023.

Written mainly in German and partly in Latin, the town or chamberlain accounts of historical Pozsony/Pressburg (present-day Bratislava), almost continuously available between 1434-1435 and 1595, contain daily/weekly resolution data on Danube floods, snow and ice cover and occasional data on rainfall, strong winds, (unintentional) fires, cold days and low flows of the Danube. The source provides systematic, annual accounts of incomes and expenses, with only a few years missing: flood and weather related reports were mainly included in the bridge masters’, the ice-cutters’, the ferrymen’s, the town messengers’, and the road and wall maintenance accounts. Furthermore, weather and water-level related information occasionally was also identified in other sections of the accounts, regarding smaller bridges, river transportation, fishing, meadows and hayfields, woods, and other utilities of the nearby island area. Because of the high density of weather and flood data and the available (mainly qualitative) descriptions, it is possible to present a three-scaled index-based quantitative reconstruction of Danube floods and, for some of the years, index reconstructions of winter severity, temperature and precipitation (rainfall, snowfall).

In the presentation, the following major topics are addressed:

• reconstruction of Danube flood intensity (three-scaled), seasonality, and flood types;
• (annual, seasonal) number of intensive rainfall and snowfall events and the (three-scaled) precipitation intensity reconstruction;
• temperature reconstruction, based on three-scaled intensity indices – primarily related to winter;
• weather extremes and corresponding hazards: strong winds and storms, (unintentional) fires, torrential rains (resulting mass erosion);
• documented Danube low-flow events, mainly reflecting on prolonged dry periods in the Upper-Danube catchment.

In the final part of the presentation, long-term climate variability processes are discussed in brief. With applying additional information available in the Bratislava area in other contemporary sources such as charters, letters, a diary (of Zsigmond Torda) and other narratives, it is possible to define periods richer in floods, hard winters and reported extreme events. Apart from the period of the early Spörer solar minimum (1430s-1440s), anomalous periods are identified around the turn of the 15^th and 16^th centuries (ca. 1480s-1510s), in the mid- and late 16^th century.

How to cite: Kiss, A.: Weather, winter severity, Danube floods and low flows at Bratislava in 1435-1595:analysis of daily/weekly resolution weather data in the Bratislava town accounts, EMS Annual Meeting 2023, Bratislava, Slovakia, 4–8 Sep 2023, EMS2023-620, https://doi.org/10.5194/ems2023-620, 2023.

The Thirty Years’ War in 1618–1648 CE was an armed military conflict in Europe resulting from culminating contradictions between advocates of Roman Catholic and Protestant Churches during reformation time of the 17th century on the one hand and power fight for European political hegemony on the other. This war meant for Europe a time of its great wide-ranging devastation. Based on documentary evidence, the paper characterises climate, weather extremes, economic and socio-political events of that time in Central Europe (nowadays Germany, Poland, Czech Republic, Slovakia, Switzerland, Austria and Hungary). Natural climate forcing indicates a gradual climate deterioration during the first half of the 17th century, related to a decrease in solar activity towards the Maunder Minimum and increased volcanic activity starting in the early 1640s. More variable temperature, precipitation and drought patterns (with respect to the 1961–1990 reference period) were typical for 1618–1648 in Central Europe. Seasonal and annual temperatures experienced cooler patterns (except summer), while spring and annual precipitation totals indicated rather drier conditions. These climatic patterns were characterised by the occurrence of many weather extremes, from which particularly late spring and early autumn frosts, heavy rain spells, followed by floods, and intense droughts were reflected in failure of grain, fruit and vine grape harvests as well as low yields of other crops. The years 1627 and 1628 are discussed as possible “years without summer”. Weather extremes caused different human impacts and responses as food shortages (reflecting harvests and prices of grain), famines and epidemics, decline in population etc. Results are discussed in a broader European context with respect to climate, weather extremes and socio-economic impacts.

How to cite: Brázdil, R., Dobrovolný, P., Pfister, C., Kleemann, K., Olinski, P., Szabó, P., and Chromá, K.: Weather and climate and their human impacts during the Thirty Years’ War in Central Europe, EMS Annual Meeting 2023, Bratislava, Slovakia, 4–8 Sep 2023, EMS2023-216, https://doi.org/10.5194/ems2023-216, 2023.

It is today undisputed that the volcanic eruption of Tambora in 1815 caused a year without summer in Central and Western Europe, which led to crop failures, inflation, disease and famine. However, little attention has been paid to the teleconnections of the great volcanic eruptions in the 17th century on agriculture and society in early modern Switzerland.

Using a regional example, the present study attempts to examine the climatological and socio-economic effects of those eruptions and the coping strategies that were developed as a result. For several centuries, the Hôpital des Bourgeois de Fribourg meticulously recorded every year all their harvests of crop, wine and dairy products - such as the famous Vacherin cheese - and the number of cattle slaughtered. These primary or secondary climate proxies can be examined for potential climatological effects.

As a public institution, the Hôpital des Bourgeois de Fribourg is strongly linked to the state of Fribourg itself. In addition to these account books, the state archive possesses an extended corpus of sources related to the history of this institution. Essential archive material, such as the Ratsmanuale (protocols) and the Mandatenbücher (regulations), allows us to draw conclusions about the socio-economic impact of the climate crises of the 17th century and the responses of the state and this important social and economic institution. These findings can then be compared with modern climate reconstruction data from the ModE-RA project – presented in a newly developed tool – to better assess the interrelation between the two. In other words, we will see how volcanoes affected Fribourg's viticulture and their Vacherin production as a result of this highly interdisciplinary approach.

How to cite: Bartlome, N.: Wine, vacherin and volcanoes: impacts of the 17th century large volcanic eruptions, EMS Annual Meeting 2023, Bratislava, Slovakia, 4–8 Sep 2023, EMS2023-575, https://doi.org/10.5194/ems2023-575, 2023.

The Diarium of the Jesuit order at Trenčín written in Latin contains systematic daily weather records (with some interruptions) from 8 November 1701 to 10 January 1710. Daily records from this period were kept by two administrators of the Jesuit dormitory (“regens convictus”) Ján Garajský and Juraj Košetič. After the death of Ján Garajský in 1702, the daily weather records are interrupted, so the winter season 1702/03 is without any weather information. With the arrival of his successor Juraj Košetič, such data appear only gradually in the course of 1703. Records related to temperature and precipitation patterns, cloudiness, as well as frequencies of different weather phenomena such as fogs, thunderstorms, strong winds. Information about floods and the occurrence of ice phenomena on the River Váh are also valuable.

In the contribution, we focus on the evaluation of the temperature patterns of individual winter seasons in this period. Winters are defined from December 1 to February 28 (or February 29). For analysis, we selected all daily data describing the temperature state of the weather. Based on this evidence, each day we classified by daily temperature indices (from -3 to +3). Although some winter seasons contain daily weather records for every single day, but not every record specifically relates to a temperature pattern. Out of a total of nine winters during this period, only 6 seasons had more than 70 percent of such daily temperature indices recorded, specifically 1703/04 (73%), 1704/05 (97%), 1705/06 (93%), 1706/07 (86%), 1707/08 (71%) and 1708/09 (81%). From them, the coldest winter season in Trenčín was 1708/09 (with cold temperature pattern), then 1704/05 and 1706/07 (with moderately cold temperature pattern), 1705/06 and 1703/04 (with mild temperature pattern), and the warmest winter season was 1707/08 (with mild temperature pattern). Overall, the coldest month was January 1709, which was also the only very cold month in this ranking. The warmest month was December 1706 with mild temperature pattern.

Like the result of the hard winter of 1708/09 was also the occurrence of ice phenomena (ice cover, ice jam with ice flood later in March) on the River Váh in Trenčín, which are recorded in the Jesuit Diary of this period.

Acknowledgment: This work was supported by the Slovak Research and Development Agency under the contract No. APVV-20-0374.

Keywords: Jesuit Diary, winter, temperature indices, cold, mild, Trenčín, ice phenomena

How to cite: Melo, M. and Marek, M.: Temperature patterns of the winters in the periods from 1703/04 to 1708/09 in Trenčín, Slovakia, EMS Annual Meeting 2023, Bratislava, Slovakia, 4–8 Sep 2023, EMS2023-349, https://doi.org/10.5194/ems2023-349, 2023.

Rebellions of peasants against nobility or social order during the 18th–19th centuries in Central Europe were usually the consequences of previous long-term societal problems. Furthermore, the general social dissatisfaction might have been often amplified by negative impacts of climate fluctuation, unfavourable weather or hydrometeorological extremes. Here, we analyse the causes of two outstanding rebellions in 1775 and 1821 in the Czech Lands with respect to climate and weather variability as well as social, economic and political issues. Analysis of both rebellions is allowed based on rich documentary evidence available for the Czech Lands in the studied period (chronicles, weather diaries, grain prices etc.). Temperature and precipitation fluctuations, the occurrence of drought and wet periods, the impacts of the Tambora eruption or changes in grain prices during 1750–1830 were taken into account.  Despite some joint causes of both uprisings (unfavourable weather, poverty, harsh corvée conditions, high taxes), each of both rebellions was characterised by its special reasons. While rainy weather, poor harvest, high grain prices and subsequent famine preceded the 1775 rebellion, the emerging agrarian crisis and sudden grain price fluctuations caused by the Tambora eruption and grain overproduction in 1818 contributed to the 1821 rebellion. The previous results of climate fluctuation will also be completed by recently published datasets and analysed from the new point of view. Moreover, former approaches to studying the causes of both rebellions will be discussed with regard to the modern ones. The results of this study contribute to a better understanding of past negative climate and weather impacts on human society and help to fill the gap in interdisciplinary research.

How to cite: Dolák, L. and Brázdil, R.: An effect of climate fluctuation on the 1775 and 1821 rebellions in the Czech Lands, EMS Annual Meeting 2023, Bratislava, Slovakia, 4–8 Sep 2023, EMS2023-464, https://doi.org/10.5194/ems2023-464, 2023.