TL;DR: Briffa as discussed by the authors was one of the most influential palaeoclimatologists of the last 30 years, whose primary research interests lay in Late-Holocene climate change with a geographical emphasis on northern Eurasia.
Abstract: Keith R. Briffa was one of the most influential palaeoclimatologists of the last 30 years. His primary research interests lay in Late-Holocene climate change with a geographical emphasis on northern Eurasia. His greatest impact was in the field of dendroclimatology, a field that he helped to shape. His contributions have been seminal to the development of sound methods for tree-ring analysis and in their proper application to allow the interpretation of climate variability from tree rings. This led to the development of many important records that allow us to understand natural climate variability on timescales from years to millennia and to set recent climatic trends in their historical context.
His primary research interests lay in late Holocene climate change with a geographical emphasis on northern Eurasia.
His contributions have been seminal to the development of sound methods for tree-ring analysis and in their proper application to allow the interpretation of climate variability from tree rings.
This led to the development of many important records that allow us to understand natural climate variability on timescales from years to millennia and to set recent climatic trends in their historical context.
TL;DR: In this article, maps of monthly self-calibrating Palmer Drought Severity Index (SC-PDSI) have been calculated for the period of 1901-2002 for Europe (35°-70°N, 10°W-60°E) with a spatial resolution of 0.5° × 0.6°.
Abstract: Maps of monthly self-calibrating Palmer Drought Severity Index (SC-PDSI) have been calculated for the period of 1901–2002 for Europe (35°–70°N, 10°W–60°E) with a spatial resolution of 0.5° × 0.5°. The recently introduced SC-PDSI is a convenient means of describing the spatial and temporal variability of moisture availability and is based on the more common Palmer Drought Severity Index. The SC-PDSI improves upon the PDSI by maintaining consistent behavior of the index over diverse climatological regions. This makes spatial comparisons of SC-PDSI values on continental scales more meaningful. Over the region as a whole, the mid-1940s to early 1950s stand out as a persistent and exceptionally dry period, whereas the mid-1910s and late 1970s to early 1980s were very wet. The driest and wettest summers on record, in terms of the amplitude of the index averaged over Europe, were 1947 and 1915, respectively, while the years 1921 and 1981 saw over 11% and over 7% of Europe suffering from extreme dry or w...
TL;DR: In this paper, an up-to-date review of instrumentally-recorded, seasonal, surface temperature change across the land and marine regions of the world during the twentieth century is presented.
Abstract: This paper is an up-to-date review of instrumentally-recorded, seasonal, surface temperature change across the land and marine regions of the world during the twentieth century. This is the first part of a two part series. The second part will deal with the interpretation of proxy-climate data in terms of large-scale hemispheric or global-scale temperature averages for the Holocene.In Part 1, we review the uncertainties associated with combining land and marine instrumental records to produce regional-average series. The surface air temperature of the world has warmed 0.5°C since the middle of the nineteenth century. The warming in the Northern Hemisphere only occurred in winter, spring and autumn. Summers are now no warmer than in the 1860s and 1870s. The same half-degree warming is seen in all seasons in the Southern Hemisphere.Spatial patterns of temperature anomalies during two warm decades, the 1930s and 1980s, all vary from season to season. Temperatures during the 1980s were by far the warmest in t...
TL;DR: The most significant and longest duration feature during the last 1200 years is the geographical extent of warmth in the middle to late 20th century as mentioned in this paper, consistent with the concepts of a Medieval Warm Period and a Little Ice Age, but comparison with instrumental temperatures shows the spatial extent of recent warmth to be of greater significance than that during the medieval period.
Abstract: Periods of widespread warmth or cold are identified by positive or negative deviations that are synchronous across a number of temperature-sensitive proxy records drawn from the Northern Hemisphere. The most significant and longest duration feature during the last 1200 years is the geographical extent of warmth in the middle to late 20th century. Positive anomalies during 890 to 1170 and negative anomalies during 1580 to 1850 are consistent with the concepts of a Medieval Warm Period and a Little Ice Age, but comparison with instrumental temperatures shows the spatial extent of recent warmth to be of greater significance than that during the medieval period.
267 citations
"In Memoriam: Keith R. Briffa, 1952-..." refers background in this paper
...…using a limited number of series that all extended back for the whole millennium (Jones et al., 1998; Juckes et al., 2007; Kaufman et al., 2009; Osborn and Briffa, 2006; Rutherford et al., 2005), as well as reconstructions of precipitation and drought patterns in mid-latitude regions (Cook et…...
TL;DR: The annual growth of trees, as represented by a variety of ringwidth, densitometric, or chemical parameters, represents a combined record of different environmental forcings, one of which is climat...
Abstract: The annual growth of trees, as represented by a variety of ringwidth, densitometric, or chemical parameters, represents a combined record of different environmental forcings, one of which is climat...
264 citations
"In Memoriam: Keith R. Briffa, 1952-..." refers background in this paper
...Keith was also the first to demonstrate that a widespread divergence between some MXD data and instrumental summer temperatures in northern high latitude had apparently occurred since about 1960 (Briffa et al., 1998c)....
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...MXD reconstructions led to better isolation of the effects of explosive volcanic eruptions (Briffa et al., 1998a) and with exact dating the realization that these events could be used to improve ice core dating (Vinther et al., 2010)....
TL;DR: In this article, the authors describe the rationale and early development of regional curve standardization (RCS) and provide some background describing the early development and development of the RCS approach.
Abstract: Some background describing the rationale and early development of regional curve standardization (RCS) is provided. It is shown how, in the application of RCS, low-frequency variance is preserved in the mean values of individual series of tree indices, while medium-frequency variance is also preserved in the slopes. Various problems in the use of the RCS approach are highlighted. The first problem arises because RCS detrending removes the average slope (derived from the data for all trees) from each individual tree measurement series. This operation results in a pervasive ‘trend-in-signal’ bias, which occurs when the underlying growth-forcing signal has variance on timescales that approach or exceed the length of the chronology. Even in a long chronology (i.e., including subfossil data), this effect will bias the start and end of the RCS chronology. Two particular problems associated with the use of RCS on contemporaneously growing trees, which might represent a typical (i.e., modern) sample, are also discussed. The first is the biasing of the RCS curve by the residual climate signal in age-aligned samples and the undesirable subsequent removal of this signal variance in RCS application. The second is the ‘differing-contemporaneous-growth-rate’ bias that effectively imparts a spurious trend over the span of a modern chronology. The first of these two can be mitigated by the application of ‘signal-free’ RCS. The second problem is more insidious and can only be overcome by the use of multiple sub-RCS curves, with a concomitant potential loss of some longer-timescale climate variance. Examples of potential biasing problems in the application of RCS are illustrated by reference to several published studies. Further implications and suggested directions for necessary further development of the RCS concept are discussed.
Briffa this paper was one of the most influential palaeoclimatologists of the last thirty years, whose primary research interests lay in late Holocene climate change with a geographical emphasis on northern Eurasia.