Fredrik Charpentier LjungqvistForskare
Fredrik Charpentier Ljungqvist är docent i både historia och i naturgeografi och knuten till Historiska institutionen och Bolincentret för klimatforskning, bägge vid Stockholms universitet, samt är Pro Futura Scientia Fellow vid Swedish Collegium for Advanced Study i Uppsala. Han forskar både inom historia och paleoklimatologi (klimathistoria) och har publicerat många vetenskapliga och populärvetenskapliga artiklar inom båda ämnena. Ljungqvist är även författare till de populärvetenskapliga böckerna Corona: Ett historiskt perspektiv på vår tids pandemi (2020), Klimatet och människan under 12 000 år (Dialogos 2017) och Den långa medeltiden (Dialogos 2015) och Global nedkylning (Norstedts 2009). Han har varit medlem av den europeiska arbetsgruppen i forskningsprogrammet Past Global Changes (PAGES) 2k, ledamot av den vetenskapliga styrgruppen för forskningsprogrammet Integrated History and Future of People on Earth (IHOPE), medlem av beredningsgruppen för historiska vetenskaper och arkeologi hos Vetenskapsrådet, samt suttit i redaktionsrådet för Historisk tidskrift. I september 2016 vann han Cliopriset för att ”förmedla färska vetenskapliga insikter till en bred publik”. Han verkade som gästforskare vid Department of Geography vid University of Cambridge, Storbritannien, oktober 2017 till april 2018 samt oktober 2018 till april 2019 och var utsedd till gästprofessor i miljövetenskap vid Lanzhou University i Kina för perioden juli 2017 till juni 2019. År 2022 tilldelades han det Rettigska priset av Kungl. Vitterhetsakademin för ”tvärvetenskapliga arbeten rörande klimat och sjukdomar i ett långtidsperspektiv som tydliggör betydelsen av humanistiska och historiska perspektiv för avgörande dagsaktuella frågor”.
Senast uppdaterat den 14 februari 2022.
ISI Web of Science [Google Scholar]
Antal indexerade publikationer: 81 
Totalt antal citeringar: 3210 
Genomsnittligt antal citeringar per publikation: 39,63 [50,32]
H-index: 24 
Högt citerade i fältet (ISI): 6
I urval från Stockholms universitets publikationsdatabas
Linking European building activity with plague history
2018. Fredrik Charpentier Ljungqvist (et al.). Journal of Archaeological Science 98, 81-92Artikel
Variations in building activity reflect demographic, economic and social change during history. Tens of thousands of wooden constructions in Europe have been dendrochronologically dated in recent decades. We use the annually precise evidence from a unique dataset of 49 640 tree felling dates of historical constructions to reconstruct temporal changes in building activity between 1250 and 1699 CE across a large part of western and central Europe largely corresponding to the former Holy Roman Empire of the German Nation. Comparison with annual records of 9772 plague outbreaks shows that construction activity was significantly negatively correlated to the number of plague outbreaks, with the greatest decrease in construction following the larger outbreaks by three to four years after the start of the epidemics. Preceding the Black Death (1346-1353 CE) by five decades and the Great Famine (1315-1322 CE) by two decades, a significant decline in construction activity at c. 1300 CE is indicative of a societal crisis, associated with population stagnation or decline. Another dramatic decline in building activity coincides with the Thirty Years' War (1618-1648 CE) and confirms the devastating nature of this conflict. While construction activity was significantly lower during periods of high grain prices, no statistically robust relationship between the number of felling dates and past temperature or hydroclimate variations is found. This study demonstrates the value of dendrochronological felling dates as an indicator for times of crisis and prosperity during periods when documentary evidence is limited.
The spatiotemporal distribution of Late Viking Age Swedish runestones
2018. Fredrik Charpentier Ljungqvist, Andrea Seim. Journal of Archaeological Science 21, 849-861Artikel
The Late Viking Age Swedish runestones are commonly acknowledged as early Christian monuments. Using geostatistical techniques and descriptive statistics, we systematically investigate the regional-to-local spatiotemporal patterns of 1302 ornamentally dated Swedish runestones regarding the timing and speed of the Christianisation process. After quantitative geostatistical analyses of the age distribution patterns of Swedish runestones, we evaluate whether the observed patterns correspond to the pace and pattern of Christianisation, as represented by the presence of mission bishoprics, early church sites, late pagan grave sites and royal estates. We identify seven distinct age groups of runestones and statistically significant regional-to-local spatiotemporal differences in the age and age spread of runestones. The oldest runestones, with the smallest age spread, are found in south-western medieval Sweden, and the youngest, as well as the largest age spread, in the north-east, respectively. We find that runestones are significantly older close to early ecclesiastical sites, regardless of the analytical level, and significantly younger near to late pagan graves. The results obtained are inconclusive as to whether runestones are older near royal estates. Our results support that the spatiotemporal patterns of runestone sites mirror the timing of the Christianisation process and that geostatistical approaches to larger archaeological or historical data sets can add new dimensions to the understanding of the spatial dimensions of past societal changes.
Klimatet och människan under 12 000 år
2017. Fredrik Charpentier Ljungqvist.Bok
I boken presenteras för första gången på svenska resultaten från den senaste klimathistoriska forskningen för en bred publik. I en välblandad mix av historia och klimatvetenskap får läsaren följa med på en medryckande resa genom världshistorien då kraftiga och plötsliga klimatförändringar emellanåt dramatiskt förändrat livsvillkoren för miljoner människor.
För 6 000 år sedan var till exempel Sahara en frodig savann i stället för världens största öken, samtidigt som klimatet var varmt nog i Sverige för sköldpaddor och vilda vindruvor. Senare under historien har stora variationer i monsunregnen i Asien gett upphov till antingen välstånd eller hungersnöd för miljontals människor.
För tusen år sedan kollapsade indianska civilisationer av torka, samtidigt som ett varmare klimat tillät nordbor att kolonisera södra Grönland. Den så kallade lilla istiden, som kulminerade på 1600-talet, orsakade försörjningskriser i Europa och Kina och på många andra håll i världen.
Författaren ger oss åtskilliga spännande och lärorika exempel på hur klimatförändringar under historien påverkat utvecklingen i olika delar av världen och hur människor hanterat eller inte hanterat konsekvenserna av klimatförändringar. Det är insikter som är mycket relevanta i vår tid.
Northern Hemisphere hydroclimate variability over the past twelve centuries
2016. Fredrik Charpentier Ljungqvist (et al.). Nature 532 (7597), 94-98Artikel
Accurate modelling and prediction of the local to continental-scale hydroclimate response to global warming is essential given the strong impact of hydroclimate on ecosystem functioning, crop yields, water resources, and economic security. However, uncertainty in hydroclimate projections remains large, in part due to the short length of instrumental measurements available with which to assess climate models. Here we present a spatial reconstruction of hydroclimate variability over the past twelve centuries across the Northern Hemisphere derived from a network of 196 at least millennium-long proxy records. We use this reconstruction to place recent hydrological changes and future precipitation scenarios in a long-term context of spatially resolved and temporally persistent hydroclimate patterns. We find a larger percentage of land area with relatively wetter conditions in the ninth to eleventh and the twentieth centuries, whereas drier conditions are more widespread between the twelfth and nineteenth centuries. Our reconstruction reveals that prominent seesaw patterns of alternating moisture regimes observed in instrumental data across the Mediterranean, western USA, and China have operated consistently over the past twelve centuries. Using an updated compilation of 128 temperature proxy records, we assess the relationship between the reconstructed centennial-scale Northern Hemisphere hydroclimate and temperature variability. Even though dry and wet conditions occurred over extensive areas under both warm and cold climate regimes, a statistically significant co-variability of hydroclimate and temperature is evident for particular regions. We compare the reconstructed hydroclimate anomalies with coupled atmosphere-ocean general circulation model simulations and find reasonable agreement during pre-industrial times. However, the intensification of the twentieth-century-mean hydroclimate anomalies in the simulations, as compared to previous centuries, is not supported by our new multi-proxy reconstruction. This finding suggests that much work remains before we can model hydroclimate variability accurately, and highlights the importance of using palaeoclimate data to place recent and predicted hydroclimate changes in a millennium-long context.
The significance of climate variability on early modern European grain prices
2022. Fredrik Charpentier Ljungqvist (et al.). Cliometrica 16, 29-77Artikel
Grain was the most important food source in early modern Europe (c. 1500-1800), and its price influenced the entire economy. The extent to which climate variability determined grain price variations remains contested, and claims of solar cycle influences on prices are disputed. We thoroughly reassess these questions, within a framework of comprehensive statistical analysis, by employing an unprecedentedly large grain price data set together with state-of-the-art palaeoclimate reconstructions and long meteorological series. A highly significant negative grain price-temperature relationship (i.e. colder = high prices and vice versa) is found across Europe. This association increases at larger spatial and temporal scales and reaches a correlation of -0.41 considering the European grain price average and previous year June-August temperatures at annual resolution, and of -0.63 at decadal timescales. This strong relationship is of episodic rather than periodic (cyclic) nature. Only weak and spatially inconsistent signals of hydroclimate (precipitation and drought), and no meaningful association with solar variations, are detected in the grain prices. The significant and persistent temperature effects on grain prices imply that this now rapidly changing climate element has been a more important factor in European economic history, even in southern Europe, than commonly acknowledged.
Climate and society in European history
2021. Fredrik Charpentier Ljungqvist, Andrea Seim, Heli Huhtamaa. Wiley Interdisciplinary Reviews 12 (2)Artikel
This article evaluates 165 studies from various disciplines, published between 2000 and 2019, which in different ways link past climate variability and change to human history in medieval and early modern Europe (here, c. 700-1815 CE). Within this review, we focus on the identification and interpretation of causal links between changes in climate and in human societies. A revised climate-society impact order model of historical climate-society interactions is presented and applied to structure the findings of the past 20 years' scholarship. Despite considerable progress in research about past climate-society relations, partly expedited by new palaeoclimate data, we identify limitations to knowledge, including geographical biases, a disproportional attention to extremely cold periods, and a focus on crises. Furthermore, recent scholarship shows that the limitations with particular disciplinary approaches can be successfully overcome through interdisciplinary collaborations. We conclude the article by proposing recommendations for future directions of research in the climatic change-human history nexus.
Climate in Nordic historical research - a research review and future perspectives
2021. Heli Huhtamaa, Fredrik Charpentier Ljungqvist. Scandinavian Journal of HistoryArtikel
This article assesses the development and current state of climate history research conducted in the five Nordic countries and Estonia. The possible societal impacts of past climatic changes already interested a handful of Nordic historians in the early twentieth century, but the lack of data on past climate fluctuations constrained scholarship in this field until recently. The data availability has increased fundamentally over the past decades due to the advances of palaeoclimatology. However, these advances have created new challenges, related to the ability to utilize data from the natural sciences in historical research as well as acquiring a basic knowledge on climatology. In many European countries, climate history has established itself as a strong academic subfield and consequently has created approaches as to how to overcome some main pitfalls, like climate determinism, related to the early works in the field. These epistemological advances are just beginning to gain a foothold in Nordic historical research. Thus, the article concludes with ten recommendations to improve future research in Nordic climate history.
Legitimising Royal Power in Medieval Scandinavian Laws
2020. Fredrik Charpentier Ljungqvist. Nordic Elites in Transformation, c. 1050–1250, Volume III, 105-126Kapitel
From the late twelfth century onwards, we observe a gradual shift from a horizontal to a vertical relationship between king and commoners in the kingdoms of Denmark, Norway, and Sweden. This gradual transformation contributed to, and partly enabled, the growth of royal power in medieval Scandinavia. As elsewhere in Europe, kingship underwent a fundamental ideological change bringing about new forms of legitimisation of royal power according to which the king functioned as a rex iustus by divine grace. This elevated position placed the king above other members of the secular elite as he was glorified as God’s elected representative on earth. This chapter explores this process by analysing the preserved law material, and placing special emphasis on mutual obligations between king and commoners, considering the extent to which the king was bound by law, individual rights to pursue feuds, royal privileges, and crimes against the Crown. It shows, among other things, how the king was bound by the law in all the three Scandinavian countries up to the thirteenth century when differences started to appear. The kings in Denmark and Sweden were increasingly restricted by specific constitutional provisions, while the kings in Norway became less and less confined by law.
The spatiotemporal distribution of historical malaria cases in Sweden
2021. Tzu Tung Chen (et al.). Malaria Journal 20 (1)Artikel
Background: Understanding of the impacts of climatic variability on human health remains poor despite a possibly increasing burden of vector-borne diseases under global warming. Numerous socioeconomic variables make such studies challenging during the modern period while studies of climate-disease relationships in historical times are constrained by a lack of long datasets. Previous studies have identified the occurrence of malaria vectors, and their dependence on climate variables, during historical times in northern Europe. Yet, malaria in Sweden in relation to climate variables is understudied and relationships have never been rigorously statistically established. This study seeks to examine the relationship between malaria and climate fluctuations, and to characterise the spatio-temporal variations at parish level during severe malaria years in Sweden 1749-1859.
Methods: Symptom-based annual malaria case/death data were obtained from nationwide parish records and military hospital records in Stockholm. Pearson (r(p)) and Spearman's rank (r(s)) correlation analyses were conducted to evaluate inter-annual relationship between malaria data and long meteorological series. The climate response to larger malaria events was further explored by Superposed Epoch Analysis, and through Geographic Information Systems analysis to map spatial variations of malaria deaths.
Results: The number of malaria deaths showed the most significant positive relationship with warm-season temperature of the preceding year. The strongest correlation was found between malaria deaths and the mean temperature of the preceding June-August (r(s) = 0.57, p < 0.01) during the 1756-1820 period. Only non-linear patterns can be found in response to precipitation variations. Most malaria hot-spots, during severe malaria years, concentrated in areas around big inland lakes and southern-most Sweden.
Conclusions: Unusually warm and/or dry summers appear to have contributed to malaria epidemics due to both indoor winter transmission and the evidenced long incubation and relapse time of P. vivax, but the results also highlight the difficulties in modelling climate-malaria associations. The inter-annual spatial variation of malaria hot-spots further shows that malaria outbreaks were more pronounced in the southern-most region of Sweden in the first half of the nineteenth century compared to the second half of the eighteenth century.