scholarly journals Temporal variations of trends in the Central England Temperature series

2020 ◽  
Vol 46 (2) ◽  
pp. 345-369 ◽  
Author(s):  
J.C. González-Hidalgo ◽  
D. Peña-Angulo ◽  
S. Beguería
Keyword(s):  
Analytical Framework ◽  
Temporal Variations ◽  
Natural Variability ◽  
Temperature Series ◽  
Ice Age ◽  
Window Length ◽  
Climate Signal ◽  
Monotonic Trend ◽  
Central England Temperature

Variations in trend rates of annual values of the Central England Temperature series (CET) over the period1659-2017 were analysed using moving windows of different length, to identify the minimum period in which the trend expresses a climate signal not hidden by the noise produced by natural variability. Trend rates exhibit high variability and irregular shifting from positive to negative values unless very long window lengths (of 100 years or more) are used. In general, as the duration of the length of the temporal window analysed increases, the absolute range of the trend rates decreases and the signal-to-noise (S/N) ratio increases. The relationship between the S/N ratio and the window length also depended on the total length of the series, so high S/N values are achieved faster when shorter time series are considered. This prevents suggesting a minimum window length for undertaking trend analyses.A comparison between CET and the average continental series in the Berkeley Earth Surface Temperature (BEST) database in their common period (1753-2017) repeats the patterns described for 1659-2017, although the average values of the rates, ranges and the "threshold period" in years change, and are more variable in CET than in BEST.Analysis of both series suggests that the recent warming started early and can be linked to the recovery of temperatures after the Little Ice Age. This process has characterised by progressively increasing trend rates, but also includes periods of deceleration or even negative trends spanning less than 50 years. The behaviour of the two long-term temperature records analysed agrees with a long-term persistence (LTP) process. We estimated the Hurst exponent of the CET series to be around 0.72 and 0.8, which reinforces the LTP hypothesis. This implies that the currently widespread statistical framework assuming a stationary, short-memory process in which departures from the norm can be easily assessed by monotonic trend analysis should not be accepted for long climatic series. In brief, relevant questions relative to the recent evolution of temperatures such as the distinction between natural variability and departures from stationarity; attribution of the causes of variability at different time scales; determination of the shortest window length to detect a trend; and other similar ones have still not been answered and may require adoption of an alternative analytical framework.

scholarly journals Climate Signal Detection Times and Constraints on Climate Benchmark Accuracy Requirements

2008 ◽  
Vol 21 (4) ◽  
pp. 841-846 ◽  
Author(s):  
Stephen S. Leroy ◽  
James G. Anderson ◽  
George Ohring
Keyword(s):  
Measurement Uncertainty ◽  
Interannual Variability ◽  
Natural Variability ◽  
Climate System ◽  
Simple Linear Regression ◽  
Climate Trends ◽  
Climate Signal ◽  
Naturally Occurring ◽  
Long Term Trends

Abstract Long-term trends in the climate system are always partly obscured by naturally occurring interannual variability. All else being equal, the larger the natural variability, the less precisely one can estimate a trend in a time series of data. Measurement uncertainty, though, also obscures long-term trends. The way in which measurement uncertainty and natural interannual variability interact in inhibiting the detection of climate trends using simple linear regression is derived and the manner in which the interaction between the two can be used to formulate accuracy requirements for satellite climate benchmark missions is shown. It is found that measurement uncertainty increases detection times, but only when considered in direct proportion to natural variability. It is also found that detection times depend critically on the correlation time of natural variability and satellite lifetime. As a consequence, requirements on satellite climate benchmark accuracy and mission lifetime must be directly related to the natural variability of the climate system and its associated correlation times.

English Weather: The Seventeenth-Century Diary of Ralph Josselin

2012 ◽  
Vol 43 (2) ◽  
pp. 221-246 ◽  
Author(s):  
Joyce Macadam
Keyword(s):  
Seventeenth Century ◽  
Tree Rings ◽  
Little Ice Age ◽  
Current Knowledge ◽  
Weather Conditions ◽  
Severe Weather ◽  
Temperature Series ◽  
Ice Age ◽  
Central England Temperature ◽  
Local Weather

The seventeenth-century diary of Ralph Josselin recorded local weather conditions in Earls Colne, Essex, during a period when some of the most severe weather of the Little Ice Age occurred. A comparison of information extracted from the journal with the instrumental findings of Josselin's contemporaries, the natural proxy of tree rings, and the highly regarded Central England Temperature series corroborates current knowledge about weather conditions during an era for which sources are problematical.

scholarly journals Adopt, adapt, or abandon technology-supported person-centred care initiatives: healthcare providers’ beliefs matter

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Kari Dyb ◽  
Gro Rosvold Berntsen ◽  
Lisbeth Kvam
Keyword(s):  
Information Technologies ◽  
Scale Up ◽  
Healthcare Providers ◽  
Healthcare Services ◽  
Analytical Framework ◽  
Development Project ◽  
Technology Support ◽  
Care Needs ◽  
Term Care

Abstract Background Technology support and person-centred care are the new mantra for healthcare programmes in Western societies. While few argue with the overarching philosophy of person-centred care or the potential of information technologies, there is less agreement on how to make them a reality in everyday clinical practice. In this paper, we investigate how individual healthcare providers at four innovation arenas in Scandinavia experienced the implementation of technology-supported person-centred care for people with long-term care needs by using the new analytical framework nonadoption, abandonment, and challenges to the scale-up, spread, and sustainability (NASSS) of health and care technologies. We also discuss the usability and sensitivity of the NASSS framework for those seeking to plan, implement, and evaluate technology-supported healthcare programmes. This study is part of an interdisciplinary research and development project called Patients and Professionals in Partnership (2016–2020). It originates at one of ten work packages in this project. Method The main data consist of ethnographic field observations at the four innovation arenas and 29 interviews with involved healthcare providers. To ensure continuous updates and status on work in the four innovation arenas, we have also participated in a total of six annual network meetings arranged by the project. Results While the NASSS framework is very useful for identifying and communicating challenges with the adoption and spread of technology-supported person-centred care initiatives, we found it less sensitive towards capturing the dedication, enthusiasm, and passion for care transformation that we found among the healthcare providers in our study. When it comes to technology-supported person-centred care, the point of no return has passed for the involved healthcare providers. To them, it is already a definite part of the future of healthcare services. How to overcome barriers and obstacles is pragmatically approached. Conclusion Increased knowledge about healthcare providers and their visions as potential assets for care transformation might be critical for those seeking to plan, implement, and evaluate technology-supported healthcare programmes.

scholarly journals Surface Water Temperature Predictions at a Mid-Latitude Reservoir under Long-Term Climate Change Impacts Using a Deep Neural Network Coupled with a Transfer Learning Approach

Water ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1109
Author(s):  
Nobuaki Kimura ◽  
Kei Ishida ◽  
Daichi Baba
Keyword(s):  
Climate Change ◽  
Surface Water ◽  
Water Temperature ◽  
Transfer Learning ◽  
Air Temperature ◽  
Climate Models ◽  
Temporal Variations ◽  
Training Data ◽  
Surface Water Temperature

Long-term climate change may strongly affect the aquatic environment in mid-latitude water resources. In particular, it can be demonstrated that temporal variations in surface water temperature in a reservoir have strong responses to air temperature. We adopted deep neural networks (DNNs) to understand the long-term relationships between air temperature and surface water temperature, because DNNs can easily deal with nonlinear data, including uncertainties, that are obtained in complicated climate and aquatic systems. In general, DNNs cannot appropriately predict unexperienced data (i.e., out-of-range training data), such as future water temperature. To improve this limitation, our idea is to introduce a transfer learning (TL) approach. The observed data were used to train a DNN-based model. Continuous data (i.e., air temperature) ranging over 150 years to pre-training to climate change, which were obtained from climate models and include a downscaling model, were used to predict past and future surface water temperatures in the reservoir. The results showed that the DNN-based model with the TL approach was able to approximately predict based on the difference between past and future air temperatures. The model suggested that the occurrences in the highest water temperature increased, and the occurrences in the lowest water temperature decreased in the future predictions.

scholarly journals CO2 dynamics and heterogeneity in a cave atmosphere: role of ventilation patterns and airflow pathways

2021 ◽  
Author(s):  
Lovel Kukuljan ◽  
Franci Gabrovšek ◽  
Matthew D. Covington ◽  
Vanessa E. Johnston
Keyword(s):  
Temporal Variations ◽  
Observation Point ◽  
Spatially Distributed ◽  
Combined Action ◽  
Karst Systems ◽  
The Relationship ◽  
Co2 Dynamics ◽  
Global Carbon

AbstractUnderstanding the dynamics and distribution of CO2 in the subsurface atmosphere of carbonate karst massifs provides important insights into dissolution and precipitation processes, the role of karst systems in the global carbon cycle, and the use of speleothems for paleoclimate reconstructions. We discuss long-term microclimatic observations in a passage of Postojna Cave, Slovenia, focusing on high spatial and temporal variations of pCO2. We show (1) that the airflow through the massif is determined by the combined action of the chimney effect and external winds and (2) that the relationship between the direction of the airflow, the geometry of the airflow pathways, and the position of the observation point explains the observed variations of pCO2. Namely, in the terminal chamber of the passage, the pCO2 is low and uniform during updraft, when outside air flows to the site through a system of large open galleries. When the airflow reverses direction to downdraft, the chamber is fed by inlets with diverse flow rates and pCO2, which enter via small conduits and fractures embedded in a CO2-rich vadose zone. If the spatial distribution of inlets and outlets produces minimal mixing between low and high pCO2 inflows, high and persistent gradients in pCO2 are formed. Such is the case in the chamber, where vertical gradients of up to 1000 ppm/m are observed during downdraft. The results presented in this work provide new insights into the dynamics and composition of the subsurface atmosphere and demonstrate the importance of long-term and spatially distributed observations.

scholarly journals Slavery and Its Transformations: Prolegomena for a Global and Comparative Research Agenda

2021 ◽  
Vol 63 (3) ◽  
pp. 566-598
Author(s):  
Matthias van Rossum
Keyword(s):  
Comparative Research ◽  
Research Agenda ◽  
Analytical Framework ◽  
The Body ◽  
Indonesian Archipelago ◽  
Research Perspectives ◽  
History Of ◽  
The Indian Ocean ◽  
Contemporary Development

AbstractThis article argues that we need to move beyond the “Atlantic” and “formal” bias in our understanding of the history of slavery. It explores ways forward toward developing a better understanding of the long-term global transformations of slavery. Firstly, it claims we should revisit the historical and contemporary development of slavery by adopting a wider scope that accounts for the adaptable and persistent character of different forms of slavery. Secondly, it stresses the importance of substantially expanding the body of empirical observations on trajectories of slavery regimes, especially outside the Atlantic, and most notable in the Indian Ocean and Indonesian Archipelago worlds, where different slavery regimes existed and developed in interaction. Thirdly, it proposes an integrated analytical framework that will overcome the current fragmentation of research perspectives and allow for a more comparative analysis of the trajectories of slavery regimes in their highly diverse formal and especially informal manifestations. Fourth, the article shows how an integrated framework will enable a collaborative research agenda that focuses not only on comparisons, but also on connections and interactions. It calls for a closer integration of the histories of informal slavery regimes into the wider body of existing scholarship on slavery and its transformations in the Atlantic and other more intensely studied formal slavery regimes. In this way, we can renew and extend our understandings of slavery's long-term, global transformations.

Holocene eolian sand deposition linked to climatic variability, Northern Great Plains, Canada

The Holocene ◽  
2016 ◽  
Vol 27 (4) ◽  
pp. 579-593 ◽  
Author(s):  
Stephen A Wolfe ◽  
Olav B Lian ◽  
Christopher H Hugenholtz ◽  
Justine R Riches
Keyword(s):  
Great Plains ◽  
Climatic Variability ◽  
Sediment Cores ◽  
Soil Formation ◽  
Temporal Variations ◽  
Ice Age ◽  
Northern Great Plains ◽  
Eolian Sand ◽  
Sand Accumulation ◽  
Sand Deposition

The Bigstick and Seward Sand Hills are possibly two of the oldest dune fields within the late Wisconsin glaciated regions of the Northern Great Plains. As with most Northern Great Plains dune fields, source sediments are former proglacial outwash sands. Thus, Holocene dune construction is primarily related to spatial–temporal variations in surface cover and transport capacity, rather than renewed sediment input. However, eolian landscape reconstructions on the Northern Great Plains have been temporally constrained to recent periods of activity, as older episodes of deposition are typically reworked by younger events. In this study, sediment cores from shallow lacustrine basins and interdune areas provide an improved record of Holocene eolian sand deposition. Eolian sand accumulation in the interdunes and basins occurred between 150 and 270 years ago, 1.9 and 3.0 ka, 5.4 and 8.6 ka, and prior to ca. 10.8 ka. These episodes of sand accumulation were bracketed by lacustrine deposition and soil formation, which represented wetter conditions. Other than mid-Holocene dune activity, which may be related to peak warmth and aridity, most periods of eolian sand accumulation coincided with cooler but drier climatic events such as the Younger Dryas, late-Holocene cooling prior to the Medieval Climatic Anomaly, and the ‘Little Ice Age’. These depositional episodes are also spatially represented by other dune fields in the region, providing a broad-scale view of the connections between past climatic events and eolian landscape evolution on the Northern Great Plains.

scholarly journals Nudibranchs out of water: long-term temporal variations in the abundance of two Dendrodoris species under emersion

2018 ◽  
Vol 72 (1) ◽  
Author(s):  
Ricardo Cyrne ◽  
Inês C. Rosa ◽  
Filipa Faleiro ◽  
Gisela Dionísio ◽  
Miguel Baptista ◽  
...  
Keyword(s):  
Temporal Variations

scholarly journals Content analysis for <i>Agricultural Records</i> of the United Kingdom, AD 200 to 1977: a study of frequency in human records concerning climate phenomenon

2011 ◽  
Vol 7 (4) ◽  
pp. 2555-2577
Author(s):  
D. H. Holt
Keyword(s):  
Content Analysis ◽  
Ice Age ◽  
Climate Data ◽  
The United Kingdom ◽  
Weather Phenomenon ◽  
Continuous Record ◽  
Frequency Occurrence ◽  
The Uk ◽  
Climate Events

Abstract. A content analysis has been completed on a text from the UK that has gathered agricultural and climate data from the years AD 220 to 1977 from 100s of sources. The content analysis coded all references to climate and agriculture to ascertain which climate events were recorded and which were not. This study addressed the question: is there bias in human records of climate? This evaluated the continuous record (AD 1654–1977), discontinous record (AD 220–1653), the whole record (AD 220–1977), the Little Climate Optimum (AD 850–1250) and the Little Ice Age (AD 1450–1880). This study shows that there is no significant variation in any of these periods in frequency occurrence of "good" or "bad" climate suggesting humans are not recording long-term changes in climate, but they are recording weather phenomenon as it occurs.

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