Trends in extremes of temperature, dew point and precipitation from long instrumental records from central Europe

For the analysis of trends in weather extremes, we introduce a diagnostic variable, the exceedance product, which combines intensity and frequency of extremes. We separate trends in higher moments from trends in mean or standard deviation and use bootstrap resampling to evaluate statistical significances. Application to daily meteorological records from Potsdam (1893–2005) and Prague (1775–2004) reveals that extremely cold winters occurred only until mid-20th century, whereas warm winters show upward trends. These were significant changes in higher moments of the temperature distribution. In contrast, trends in summer temperature extremes (e.g., 2003 European heatwave), can be explained by linear changes in mean or standard deviation. While precipitation at Potsdam does not exhibit pronounced trends, dew point displays an enigmatic change from maximum extremes during the 1960s to minimum extremes during the 1970s.Zur Untersuchung von Trends vonWetterextremen wird ein neuartiges „Wirkungsmaß” eingeführt, das Produkt der Extremwertübertreffung, welches die beiden Aspekte „Stärke” und „Häufigkeit” miteinander verbindet. Es werden Trends in höheren Momenten von Trends in Mittelwert und Standardabweichung getrennt sowie Bootstrap-Verfahren angewendet, um die statistische Signifikanz auszuwerten. Bei der Verwendung von meteorologischen Daten in täglicher Auflösung von Potsdam (1893–2005) und Prag (1775–2004) zeigt sich, dass extrem kalte Winter nur bis Mitte des 20. Jahrhundert auftraten, wohingegen warme Winter einen Aufwärtstrend aufweisen, welche signifikante Änderungen in höheren Momenten der Temperaturverteilung darstellen. Im Gegensatz dazu kann der Trend von Sommer-Temperaturextremen (z.B. die Hitzewelle im Jahr 2003 in Europa) durch Änderungen in Mittelwert und Standardabweichung erklärt werden. Während der Niederschlag in Potsdam keine ausgeprägte Trends zeigt, weist der Taupunkt einen rätselhaften Übergang von Maximumextremen in den 1960ern zu Minimumextremen in den 1970ern auf

Multidecadal climate variability over northern France during the past 500 years and its relation to large-scale atmospheric circulation

(IF 3.76; Q1)International audienceWe examine secular changes and multidecadal climate variability on a seasonal scale in northern France over the last 500 years and examine the extent to which they are driven by large‐scale atmospheric variability. Multiscale trend analysis and segmentation procedures show statistically significant increases of winter and spring precipitation amounts in Paris since the end of the 19th century. This changes the seasonal precipitation distribution from one with a pronounced summer peak at the end of the Little Ice Age to an almost uniform distribution in the 20th century. This switch is linked to an early warming trend in winter temperature. Changes in spring precipitation are also correlated with winter precipitation for time scales greater than 50 years, which suggests a seasonal persistence. Hydrological modelling results show similar rising trends in river flow for the Seine at Paris. However, such secular trends in the seasonal climatic conditions over northern France are substantially modulated by irregular multidecadal (50–80 years) fluctuations. Furthermore, since the end of the 19th century, we find an increasing variance in multidecadal hydroclimatic winter and spring, and this coincides with an increase in the multidecadal North Atlantic Oscillation (NAO) variability, suggesting a significant influence of large‐scale atmospheric circulation patterns. However, multidecadal NAO variability has decreased in summer. Using Empirical Orthogonal Function analysis, we detect multidecadal North Atlantic sea‐level pressure anomalies, which are significantly linked to the NAO during the Modern period. In particular, a south‐eastward (south‐westward) shift of the Icelandic Low (Azores High) drives substantial multidecadal changes in spring. Wetter springs are likely to be driven by potential changes in moisture advection from the Atlantic, in response to northward shifts of North Atlantic storm tracks over European regions, linked to periods of positive NAO. Similar, but smaller, changes in rainfall are observed in winter

Trends in extremes of temperature, dew point and precipitation from long instrumental records from central Europe

For the analysis of trends in weather extremes, we introduce a diagnostic variable, the exceedance product, which combines intensity and frequency of extremes. We separate trends in higher moments from trends in mean or standard deviation and use bootstrap resampling to evaluate statistical significances. Application to daily meteorological records from Potsdam (1893–2005) and Prague (1775–2004) reveals that extremely cold winters occurred only until mid-20th century, whereas warm winters show upward trends. These were significant changes in higher moments of the temperature distribution. In contrast, trends in summer temperature extremes (e.g., 2003 European heatwave), can be explained by linear changes in mean or standard deviation. While precipitation at Potsdam does not exhibit pronounced trends, dew point displays an enigmatic change from maximum extremes during the 1960s to minimum extremes during the 1970s.Zur Untersuchung von Trends vonWetterextremen wird ein neuartiges „Wirkungsmaß” eingeführt, das Produkt der Extremwertübertreffung, welches die beiden Aspekte „Stärke” und „Häufigkeit” miteinander verbindet. Es werden Trends in höheren Momenten von Trends in Mittelwert und Standardabweichung getrennt sowie Bootstrap-Verfahren angewendet, um die statistische Signifikanz auszuwerten. Bei der Verwendung von meteorologischen Daten in täglicher Auflösung von Potsdam (1893–2005) und Prag (1775–2004) zeigt sich, dass extrem kalte Winter nur bis Mitte des 20. Jahrhundert auftraten, wohingegen warme Winter einen Aufwärtstrend aufweisen, welche signifikante Änderungen in höheren Momenten der Temperaturverteilung darstellen. Im Gegensatz dazu kann der Trend von Sommer-Temperaturextremen (z.B. die Hitzewelle im Jahr 2003 in Europa) durch Änderungen in Mittelwert und Standardabweichung erklärt werden. Während der Niederschlag in Potsdam keine ausgeprägte Trends zeigt, weist der Taupunkt einen rätselhaften Übergang von Maximumextremen in den 1960ern zu Minimumextremen in den 1970ern auf

Trends in extremes of temperature, dew point and precipitation from long instrumental records from central Europe

For the analysis of trends in weather extremes, we introduce a diagnostic variable, the exceedance product, which combines intensity and frequency of extremes. We separate trends in higher moments from trends in mean or standard deviation and use bootstrap resampling to evaluate statistical significances. Application to daily meteorological records from Potsdam (1893–2005) and Prague (1775–2004) reveals that extremely cold winters occurred only until mid-20th century, whereas warm winters show upward trends. These were significant changes in higher moments of the temperature distribution. In contrast, trends in summer temperature extremes (e.g., 2003 European heatwave), can be explained by linear changes in mean or standard deviation. While precipitation at Potsdam does not exhibit pronounced trends, dew point displays an enigmatic change from maximum extremes during the 1960s to minimum extremes during the 1970s.Zur Untersuchung von Trends vonWetterextremen wird ein neuartiges „Wirkungsmaß” eingeführt, das Produkt der Extremwertübertreffung, welches die beiden Aspekte „Stärke” und „Häufigkeit” miteinander verbindet. Es werden Trends in höheren Momenten von Trends in Mittelwert und Standardabweichung getrennt sowie Bootstrap-Verfahren angewendet, um die statistische Signifikanz auszuwerten. Bei der Verwendung von meteorologischen Daten in täglicher Auflösung von Potsdam (1893–2005) und Prag (1775–2004) zeigt sich, dass extrem kalte Winter nur bis Mitte des 20. Jahrhundert auftraten, wohingegen warme Winter einen Aufwärtstrend aufweisen, welche signifikante Änderungen in höheren Momenten der Temperaturverteilung darstellen. Im Gegensatz dazu kann der Trend von Sommer-Temperaturextremen (z.B. die Hitzewelle im Jahr 2003 in Europa) durch Änderungen in Mittelwert und Standardabweichung erklärt werden. Während der Niederschlag in Potsdam keine ausgeprägte Trends zeigt, weist der Taupunkt einen rätselhaften Übergang von Maximumextremen in den 1960ern zu Minimumextremen in den 1970ern auf

Cross-disciplinary working in the sciences and humanities: historical data rescue activities in Southeast Asia and beyond

Abstract This paper argues that more work is needed to facilitate cross-disciplinary collaborations by scholars across the physical sciences and humanities to improve Data Rescue Activities (DARE). Debate over the scale and potential impact of anthropogenic global warming is one of the dominant narratives of the twenty-first century. Predicting future climates and determining how environment and society might be affected by climate change are global issues of social, economic and political importance. They require responses from different research communities and necessitate closer inter-disciplinary working relationships for an integrated approach. Improving the datasets required for long-term climate models is an important part of this process. Establishing a multi-disciplinary dialogue and approach to DARE activities is increasingly being recognised as the best way to achieve this. This paper focuses on the recovery of the long-term instrumental weather observations used for models and reconstructions of the climate over the past two-hundred years. Written from the perspective of an historian working in the field, it does not seek to explore the reconstructions themselves but the process of data gathering, advocating a closer working relationship between the arts, social sciences, and sciences to extend the geographic and temporal coverage of extant datasets. This is especially important for regions where data gaps exist currently. First, it will offer a justification for extending data recovery activities for Southeast Asia and the China Seas region. Second, it will offer a brief overview of the data recovery projects currently operating in that area and the typesof historic source material that are used. Third, it will explore the work currently being undertaken for Southeast Asia and China under the Atmospheric Circulation Reconstructions over the Earth initiative as an example of a successful cross-disciplinary program. Finally, it will argue the importance of advertising DARE activities across different fields and the benefits of a more joined-up discussion on potential data sources by exploring the use of the resource by the wider academic community