Long-term trends in maximum, minimum and mean annual air temperatures across the Northwestern Himalaya during the twentieth century

2007 ◽  
Vol 85 (1-2) ◽  
pp. 159-177 ◽  
Author(s):  
M. R. Bhutiyani ◽  
Vishwas S. Kale ◽  
N. J. Pawar
Keyword(s):  
Twentieth Century ◽  
Air Temperatures ◽  
Long Term Trends ◽  
Maximum Minimum

On fragile democracy: Contemporary and historical perspectives—Introduction

2019 ◽  
Vol 17 (4) ◽  
pp. 422-431
Author(s):  
Martin Conway
Keyword(s):  
Twentieth Century ◽  
Special Issue ◽  
Historical Perspectives ◽  
Alternative Means ◽  
History Of ◽  
Long Term Trends

The concept of fragility provides an alternative means of approaching the history of democracy, which has often been seen as the ineluctable consequence of Europe’s social and political modernisation. This is especially so in Scandinavia, as well as in Finland, where the emergence of a particular Nordic model of democracy from the early decades of the twentieth century onwards has often been explained with reference to embedded traditions of local self-government and long-term trends towards social egalitarianism. In contrast, this article emphasises the tensions present within the practices and understandings of democracy in the principal states of Scandinavia during the twentieth century. In doing so, it provides an introduction to the articles that compose this Special Issue, as well as contributing to the wider literature on the fragility of present-day structures of democracy.

scholarly journals GPRChinaTemp1km: a high-resolution monthly air temperature dataset for China (1951–2020) based on machine learning

2021 ◽  
Author(s):  
Qian He ◽  
Ming Wang ◽  
Kai Liu ◽  
Kaiwen Li ◽  
Ziyu Jiang
Keyword(s):  
Machine Learning ◽  
Gaussian Process ◽  
Air Temperature ◽  
Spatial Interpolation ◽  
Gaussian Process Regression ◽  
Temperature Data ◽  
Air Temperatures ◽  
Maximum Air Temperature ◽  
Maximum Minimum

Abstract. An accurate spatially continuous air temperature dataset is crucial for multiple applications in environmental and ecological sciences. Existing spatial interpolation methods have relatively low accuracy and the resolution of available long-term gridded products of air temperature for China is coarse. Point observations from meteorological stations can provide long-term air temperature data series but cannot represent spatially continuous information. Here, we devised a method for spatial interpolation of air temperature data from meteorological stations based on powerful machine learning tools. First, to determine the optimal method for interpolation of air temperature data, we employed three machine learning models: random forest, support vector machine, and Gaussian process regression. Comparison of the mean absolute error, root mean square error, coefficient of determination, and residuals revealed that Gaussian process regression had high accuracy and clearly outperformed the other two models regarding interpolation of monthly maximum, minimum, and mean air temperatures. The machine learning methods were compared with three traditional methods used frequently for spatial interpolation: inverse distance weighting, ordinary kriging, and ANUSPLIN. Results showed that the Gaussian process regression model had higher accuracy and greater robustness than the traditional methods regarding interpolation of monthly maximum, minimum, and mean air temperatures in each month. Comparison with the TerraClimate, FLDAS, and ERA5 datasets revealed that the accuracy of the temperature data generated using the Gaussian process regression model was higher. Finally, using the Gaussian process regression method, we produced a long-term (January 1951 to December 2020) gridded monthly air temperature dataset with 1 km resolution and high accuracy for China, which we named GPRChinaTemp1km. The dataset consists of three variables: monthly mean air temperature, monthly maximum air temperature, and monthly minimum air temperature. The obtained GPRChinaTemp1km data were used to analyse the spatiotemporal variations of air temperature using Theil–Sen median trend analysis in combination with the Mann–Kendall test. It was found that the monthly mean and minimum air temperatures across China were characterized by a significant trend of increase in each month, whereas monthly maximum air temperature showed a more spatially heterogeneous pattern with significant increase, non-significant increase, and non-significant decrease. The GPRChinaTemp1km dataset is publicly available at https://doi.org/10.5281/zenodo.5112122 (He et al., 2021a) for monthly maximum air temperature, at https://doi.org/10.5281/zenodo.5111989 (He et al., 2021b) for monthly mean air temperature and at https://doi.org/10.5281/zenodo.5112232 (He et al., 2021c) for monthly minimum air temperature.

Intergenerational Social Mobility in Twentieth-Century Spain

2020 ◽  
pp. 224-250
Author(s):  
Carlos J. Gil-Hernández ◽  
Fabrizio Bernardi ◽  
Ruud Luijkx
Keyword(s):  
Twentieth Century ◽  
Structural Changes ◽  
Educational Expansion ◽  
Class Mobility ◽  
Political Modernization ◽  
Long Term Trends ◽  
Modernization Process ◽  
The 1960S ◽  
Social Fluidity

This chapter studies long-term trends in intergenerational class mobility in Spain across the twentieth century drawing from a large pooled dataset (n = 81,475). From the 1960s, Spain underwent a late but intense economic, cultural, and political modernization process. During this period of far-reaching institutional change, men and women experienced a significant increase in upward mobility rates and social fluidity: steady and substantial for women, more modest for men. We disentangle different pathways driving this change in social fluidity using counterfactual simulations. The main drivers of the observed equalization of opportunities were the educational expansion and the direct effect of social origins. We argue that women were particularly benefited from dramatic structural changes in labor force participation, occupational upgrading, and educational expansion in which more room at the top allowed disadvantaged social classes to depart from their origins.

scholarly journals Inconsistencies between Long-Term Trends in Storminess Derived from the 20CR Reanalysis and Observations

2013 ◽  
Vol 26 (3) ◽  
pp. 868-874 ◽  
Author(s):  
Oliver Krueger ◽  
Frederik Schenk ◽  
Frauke Feser ◽  
Ralf Weisse
Keyword(s):  
Twentieth Century ◽  
Climate Variability ◽  
Climate Models ◽  
Reanalysis Dataset ◽  
Northeast Atlantic ◽  
Long Term Trends ◽  
Storm Index ◽  
Global Reanalysis ◽  
Long Term Trend

Abstract Global atmospheric reanalyses have become a common tool for both validation of climate models and diagnostic studies, such as assessing climate variability and long-term trends. Presently, the Twentieth Century Reanalysis (20CR), which assimilates only surface pressure reports, sea ice, and sea surface temperature distributions, represents the longest global reanalysis dataset available covering the period from 1871 to the present. Currently the 20CR dataset is extensively used for the assessment of climate variability and trends. Here, the authors compare the variability and long-term trends in northeast Atlantic storminess derived from 20CR and from observations. A well-established storm index derived from pressure observations over a relatively densely monitored marine area is used. It is found that both variability and long-term trends derived from 20CR and from observations are inconsistent. In particular, both time series show opposing trends during the first half of the twentieth century: both storm indices share a similar behavior only for the more recent periods. While the variability and long-term trend derived from the observations are supported by a number of independent data and analyses, the behavior shown by 20CR is quite different, indicating substantial inhomogeneities in the reanalysis, most likely caused by the increasing number of observations assimilated into 20CR over time. The latter makes 20CR likely unsuitable for the identification of trends in storminess in the earlier part of the record, at least over the northeast Atlantic. The results imply and reconfirm previous findings that care is needed in general when global reanalyses are used to assess long-term changes.

The potential effects of anthropogenic climate change on evaporation from water storage reservoirs within the Lockyer Catchment, south-east Queensland, Australia

2016 ◽  
Vol 67 (10) ◽  
pp. 1512 ◽  
Author(s):  
Ryan McGloin ◽  
Hamish McGowan ◽  
David McJannet
Keyword(s):  
Climate Change ◽  
Water Storage ◽  
Annual Runoff ◽  
Anthropogenic Climate Change ◽  
Annual Rainfall ◽  
Air Temperatures ◽  
Storage Reservoirs ◽  
The Future ◽  
Long Term Trends

In order to effectively manage water storage reservoirs, it is essential to be able to anticipate how components of the water balance will react to predicted long-term trends in climate. This study examines the potential impacts of anthropogenic climate change on evaporation from small reservoirs in the Lockyer catchment, a productive agricultural region in south-east Queensland, Australia. Future projections of evaporation, made using the most likely future emissions scenario, suggested that evaporation is expected to increase by ~6% by the year 2050. In addition, rainfall is expected to decrease by ~8%. These projected increases in evaporation and reductions in rainfall, combined with the knowledge that changes in annual rainfall are known to be amplified in annual runoff, mean that the availability of water resources in the Lockyer catchment region may be greatly diminished in the future. In addition, increases in water scarcity, combined with higher future air temperatures and population growth, are likely to result in a greater demand for irrigation in the future.

Long-term trends in hypolimnetic volumes and dissolved oxygen concentrations in Boreal Shield lakes of south-central Ontario, Canada

2019 ◽  
Vol 76 (12) ◽  
pp. 2315-2325 ◽  
Author(s):  
Clare Nelligan ◽  
Adam Jeziorski ◽  
Kathleen M. Rühland ◽  
Andrew M. Paterson ◽  
John P. Smol
Keyword(s):  
Dissolved Oxygen ◽  
Climatic Factors ◽  
Thermocline Depth ◽  
South Central ◽  
Air Temperatures ◽  
Hypolimnetic Oxygen ◽  
Long Term Trends ◽  
Shield Lakes ◽  
Carbon Concentrations

Temperature–oxygen profiles, collected biweekly to monthly for ∼40 years, were used to calculate end-of-summer volume-weighted hypolimnetic oxygen (VWHO) concentrations in six small lakes located in south-central Ontario, Canada. Coherent decreases in thermocline depth and increases in hypolimnetic volume, mean hypolimnetic dissolved oxygen (DO) concentration, and VWHO were observed in five of the six study lakes. All lakes underwent an abrupt increase in VWHO and mean hypolimnetic DO after 2010. In four of the six study lakes, the highest hypolimnetic DO concentrations were observed in years where chlorophyll a concentrations were low, whereas at five of the six study lakes the highest hypolimnetic volumes were observed when dissolved organic carbon concentrations were relatively high. Warmer spring or winter air temperatures were associated with higher hypolimnetic DO concentrations at two sites, and longer ice-free periods were associated with smaller hypolimnetic volumes at two sites. These results suggest that the recent VWHO increases in the studied south-central Ontario lakes may be a function of multiple drivers that include changes in primary production, lake water transparency, and regional climatic factors.

Labour and the Left in the 1980s

2018 ◽  
Keyword(s):  
Twentieth Century ◽  
The Political ◽  
Class Politics ◽  
Global Context ◽  
History Of ◽  
Long Term Trends

The Introduction establishes the themes of the volume but also makes an argument about how the history of Labour and the left in the 1980s might develop. It surveys the challenges for the left in the age of Thatcherism, interpreting them from the perspective of long term trends in the history of Labour and class politics in the twentieth century but also within the global context. The Introduction makes the case that the left was not an irrelevant force and that it played a major role in constructing the political and social arguments of our time.

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