Blar i Bergen Open Research Archive på forfatter "Birks, Harry John Betteley"
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Approaches to pollen taxonomic harmonisation in Quaternary palynology
Birks, Harry John Betteley; Bhatta, Kuber Prasad; Felde, Vivian Astrup; Flantua, Suzette; Mottl, Ondrej; Haberle, Simon G.; Herbert, Annika; Hooghiemstra, Henry; Birks, Hilary H; Grytnes, John Arvid; Seddon, Alistair William Robin (Journal article; Peer reviewed, 2023)Pollen taxonomic harmonisation involves the standardisation of the nomenclature of pollen and fern spores with similar morphotypes at the determination level that is common to all grains or spores with that morphotype ... -
Arctic Holocene proxy climate database – New approaches to assessing geochronological accuracy and encoding climate variables
Sundqvist, H.S.; Kaufmann, Darrell; MaKay, Nickholas; Axford, Y.; Balascio, Nickholas; Briner, Jason P.; Cwynar, L.C.; Sejrup, Hans Petter; Subetto, D.A.; Andrews, J.T.; Bakke, Jostein; Birks, Harry John Betteley; Brooks, S.J.; Vernal, A.E.; Jennings, A.E.; Ljungvist, K.M.; Rûhland, K.M.; Saenger, C.; Smol, J.P.; Viau, A.E. (Peer reviewed; Journal article, 2014-08-29)We present a systematic compilation of previously published Holocene proxy climate records from the Arctic. We identified 170 sites from north of 58° N latitude where proxy time series extend back at least to 6 cal ka (all ... -
A brief history of climate – the northern seas from the Last Glacial Maximum to global warming
Eldevik, Tor; Risebrobakken, Bjørg; Bjune, Anne Elisabeth; Andersson, Carin; Birks, Harry John Betteley; Dokken, Trond Martin; Drange, Helge; Glessmer, Mirjam Sophia; Li, Camille; Nilsen, Jan Even Øie; Otterå, Odd Helge; Richter, Kristin; Skagseth, Øystein (Peer reviewed; Journal article, 2014-12)The understanding of climate and climate change is fundamentally concerned with two things: a well-defined and sufficiently complete climate record to be explained, for example of observed temperature, and a relevant ... -
BUMPER v1.0: A Bayesian user-friendly model for palaeo-environmental reconstruction
Holden, Philip B.; Birks, Harry John Betteley; Brooks, Stephen J.; Bush, Mark B.; Hwang, Grace M.; Matthews-Bird, Frazer; Valencia, Bryan G.; van Woesik, Robert (Peer reviewed; Journal article, 2017-02-01)We describe the Bayesian user-friendly model for palaeo-environmental reconstruction (BUMPER), a Bayesian transfer function for inferring past climate and other environmental variables from microfossil assemblages. BUMPER ... -
Chemical variations in Quercus pollen as a tool for taxonomic identification: Implications for long-term ecological and biogeographical research
Muthreich, Florian; Zimmermann, Boris; Birks, Harry John Betteley; Vila-Vicosa, Carlos M; Seddon, Alistair (Journal article; Peer reviewed, 2020)Aim Fossil pollen is an important tool for understanding biogeographical patterns in the past, but the taxonomic resolution of the fossil‐pollen record may be limited to genus or even family level. Chemical analysis of ... -
Chironomids, temperature and numerical models: a reply to Seppälä
Korhola, Atte; Birks, Harry John Betteley; Olander, Heikki; Blom, Tom (Peer reviewed; Journal article, 2001)We reply to comments by Seppälä (2001) concerning the suitability of the surface-water temperature measurements and mean July air temperature estimates used by Olanderet al. (1999) to derive quantitative chironomid-temperature ... -
Compositional turnover and variation in Eemian pollen sequences in Europe
Felde, Vivian Astrup; Flantua, Suzette; Jenks, Cathy; Benito De Pando, Blas Manuel; de Beaulieu, Jacques Louis; Kuneš, Petr; Magri, Donatella; Nalepka, Dorota; Risebrobakken, Bjørg; ter Braak, Cajo J.F.; Allen, Judy R. M.; Granoszewski, Wojciech; Helmens, Karin F.; Huntley, Brian; Kondratienė, Ona; Kalnina, Laimdota; Kupryjanowicz, Mirosława; Malkiewicz, Małgorzata; Milner, Alice M.; Nita, Małgorzata; Noryśkiewicz, Bożena; Pidek, Irena A.; Reille, Maurice; Salonen, J. Sakari; Šeirienė, Vaida; Winter, Hanna; Tzedakis, P. Chronis; Birks, Harry John Betteley (Peer reviewed; Journal article, 2019)The Eemian interglacial represents a natural experiment on how past vegetation with negligible human impact responded to amplified temperature changes compared to the Holocene. Here, we assemble 47 carefully selected Eemian ... -
Dispersal limitations matter for microbial morphospecies
Telford, Richard J.; Vandvik, Vigdis; Birks, Harry John Betteley (Peer reviewed; Journal article, 2006)In contrast with macroorganisms, whose geographical ranges are typically restricted, many microbial species appear to have cosmopolitan distributions. This observation has been explained as a consequence of ubiquitous ... -
distantia: an open-source toolset to quantify dissimilarity between multivariate ecological time-series
Benito De Pando, Blas Manuel; Birks, Harry John Betteley (Peer reviewed; Journal article, 2020)There is a large array of methods to extract knowledge and perform ecological forecasting from ecological time‐series. However, in spite of its importance for data‐mining, pattern‐matching and ecological synthesis, methods ... -
Does pollen-assemblage richness reflect floristic richness? A review of recent developments and future challenges
Birks, Harry John Betteley; Felde, Vivian Astrup; Bjune, Anne Elisabeth; Grytnes, John-Arvid; Seppä, Heikki; Giesecke, Thomas (Peer reviewed; Journal article, 2016-05)Current interest and debate on pollen-assemblage richness as a proxy for past plant richness have prompted us to review recent developments in assessing whether modern pollen-assemblage richness reflects contemporary ... -
The dynamics of Chironomidae (Insecta: Diptera) assemblages in response to environmental change during the past 700 years on Svalbard
Brooks, Stephen J.; Birks, Harry John Betteley (Peer reviewed; Journal article, 2004)The impact of recent natural and human-induced environmental change on chironomid faunas on Svalbard has been investigated. The modern chironomid fauna was studied from surface-sediment samples collected from 23 lakes in ... -
East Asian summer monsoon precipitation variability since the last deglaciation
Chen, Fahu; Xu, Qinghai; Chen, Jianhui; Birks, Harry John Betteley; Liu, Jianbao; Zhang, Shengrui; Jin, Liya; An, Chengbang; Telford, Richard; Cao, Xianyong; Wang, Zongli; Zhang, Xiaojian; Selvaraj, Kandasamy; Lu, Houyuan; Li, Yuecong; Zheng, Zhuo; Wang, Haipeng; Zhou, Aifeng; Dong, Guanghui; Zhang, Jiawu; Huang, Xiaozhong; Bloemendal, Jan; Rao, Zhiguo (Peer reviewed; Journal article, 2015-06-18)The lack of a precisely-dated, unequivocal climate proxy from northern China, where precipitation variability is traditionally considered as an East Asian summer monsoon (EASM) indicator, impedes our understanding of the ... -
Ecological memory at millennial time-scales: the importance of data constraints, species longevity and niche features
Benito De Pando, Blas Manuel; Gil-Romera, Graciela; Birks, Harry John Betteley (Peer reviewed; Journal article, 2020)Ecological memory describes how antecedent conditions drive the dynamics of an ecological system. Palaeoecological records are paramount to understand ecological memory at millennial time‐scales, but the concept is widely ... -
Effect of uneven sampling along an environmental gradient on transfer-function performance
Telford, Richard J.; Birks, Harry John Betteley (Peer reviewed; Journal article, 2011-04-27)We investigate the effect that uneven sampling of the environmental gradient has on transfer-function performance using simulated community data. We find that cross-validated estimates of the root mean squared error of ... -
Effects of within-lake variability of fossil assemblages on quantitative chironomid-inferred temperature reconstruction
Heiri, Oliver; Birks, Harry John Betteley; Brooks, Stephen J.; Velle, Gaute; Willassen, Endre (Peer reviewed; Journal article, 2003)We studied the effects of within-lake variation of subfossil chironomid assemblages on chironomid-inferred temperatures in five lakes in southern Norway. In each lake six replicate surface-sediment samples in the deepest ... -
The environmental impact of the Minoan eruption of Santorini (Thera): statistical analysis of palaeoecological data from Golbisar, southwest Turkey
Eastwood, W. J.; Tibby, J.; Roberts, N.; Birks, Harry John Betteley; Lamb, H.F. (Peer reviewed; Journal article, 2002)A tephra layer originating from the mid-second millennium BC (3300 14C yr BP) ‘Minoan’ eruption of Santorini (or Thera) in the Aegean has been found in lake sediments at G6lhisar in southwest Turkey. Microstratigraphic ... -
Evolution of vegetation and climate variability on the Tibetan Plateau over the past 1.74 million years
Zhao, Yan; Tzedakis, P. Chronis; Li, Quan; Qin, Feng; Cui, Qiaoyu; Liang, Chen; Birks, Harry John Betteley; Liu, Yaoliang; Zhang, Zhiyong; Ge, Junyi; Zhao, Hui; Felde, Vivian Astrup; Deng, Chenglong; Cai, Maotang; Li, Huan; Ren, Weihe; Wei, Haicheng; Yang, Hanfei; Zhang, Jiawu; Yu, Zicheng; Guo, Zhengtang (Journal article; Peer reviewed, 2020)The Tibetan Plateau exerts a major influence on Asian climate, but its long-term environmental history remains largely unknown. We present a detailed record of vegetation and climate changes over the past 1.74 million years ... -
An expanded calibration model for inferring lakewater and air temperatures from fossil chironomid assemblages in northern Fennoscandia
Olander, Heikki; Birks, Harry John Betteley; Korhola, Atte; Blom, Tom (Peer reviewed; Journal article, 1999)Chironomid-temperature inference models based on an expanded data set of surface-sediment and limnological data from 53 Subarctic lakes in northern Fennoscandia have been developed using eight different numerical techniques, ... -
Exploring spatio-temporal patterns of palynological changes in Asia during the Holocene
Bhatta, Kuber Prasad; Mottl, Ondrej; Felde, Vivian Astrup; Flantua, Suzette; Birks, Hilary H; Cao, Xianyong; Chen, Fahu; Grytnes, John Arvid; Seddon, Alistair William Robin; Birks, Harry John Betteley (Journal article; Peer reviewed, 2023-05-05)Historical legacies influence present-day ecosystem composition and dynamics. It is therefore important to understand the long-term dynamics of ecosystems and their properties. Analysis of ecosystem properties during the ... -
A guide to the processing and standardization of global palaeoecological data for large-scale syntheses using fossil pollen
Flantua, Suzette; Mottl, Ondrej; Felde, Vivian Astrup; Bhatta, Kuber Prasad; Birks, Hilary H; Grytnes, John Arvid; Seddon, Alistair William Robin; Birks, Harry John Betteley (Journal article; Peer reviewed, 2023)Aim: Palaeoecological data are crucial for comprehending large-scale biodiversity patterns and the natural and anthropogenic drivers that influence them over time. Over the last decade, the availability of open-access ...