TY  - JOUR
A1  - Risbey, James S.
A1  - Lewandowsky, Stephan
A1  - Cowtan, Kevin
A1  - Oreskes, Naomi
A1  - Rahmstorf, Stefan
A1  - Jokimäki, Ari
A1  - Foster, Grant
T1  - A fluctuation in surface temperature in historical context
BT  - reassessment and retrospective on the evidence
JF  - Environmental research letters
N2  - This work reviews the literature on an alleged global warming 'pause' in global mean surface temperature (GMST) to determine how it has been defined, what time intervals are used to characterise it, what data are used to measure it, and what methods used to assess it. We test for 'pauses', both in the normally understood meaning of the term to mean no warming trend, as well as for a 'pause' defined as a substantially slower trend in GMST. The tests are carried out with the historical versions of GMST that existed for each pause-interval tested, and with current versions of each of the GMST datasets. The tests are conducted following the common (but questionable) practice of breaking the linear fit at the start of the trend interval ('broken' trends), and also with trends that are continuous with the data bordering the trend interval. We also compare results when appropriate allowance is made for the selection bias problem. The results show that there is little or no statistical evidence for a lack of trend or slower trend in GMST using either the historical data or the current data. The perception that there was a 'pause' in GMST was bolstered by earlier biases in the data in combination with incomplete statistical testing.
KW  - climate variability
KW  - climate trends
KW  - temperature fluctuation
KW  - pause hiatus
Y1  - 2018
U6  - https://doi.org/10.1088/1748-9326/aaf342
SN  - 1748-9326
VL  - 13
IS  - 12
PB  - IOP Publ. Ltd.
CY  - Bristol
ER  - 
TY  - JOUR
A1  - Frank, Dorothe A.
A1  - Reichstein, Markus
A1  - Bahn, Michael
A1  - Thonicke, Kirsten
A1  - Frank, David
A1  - Mahecha, Miguel D.
A1  - Smith, Pete
A1  - Van der Velde, Marijn
A1  - Vicca, Sara
A1  - Babst, Flurin
A1  - Beer, Christian
A1  - Buchmann, Nina
A1  - Canadell, Josep G.
A1  - Ciais, Philippe
A1  - Cramer, Wolfgang
A1  - Ibrom, Andreas
A1  - Miglietta, Franco
A1  - Poulter, Ben
A1  - Rammig, Anja
A1  - Seneviratne, Sonia I.
A1  - Walz, Ariane
A1  - Wattenbach, Martin
A1  - Zavala, Miguel A.
A1  - Zscheischler, Jakob
T1  - Effects of climate extremes on the terrestrial carbon cycle: concepts, processes and potential future impacts
JF  - Global change biology
N2  - Extreme droughts, heat waves, frosts, precipitation, wind storms and other climate extremes may impact the structure, composition and functioning of terrestrial ecosystems, and thus carbon cycling and its feedbacks to the climate system. Yet, the interconnected avenues through which climate extremes drive ecological and physiological processes and alter the carbon balance are poorly understood. Here, we review the literature on carbon cycle relevant responses of ecosystems to extreme climatic events. Given that impacts of climate extremes are considered disturbances, we assume the respective general disturbance-induced mechanisms and processes to also operate in an extreme context. The paucity of well-defined studies currently renders a quantitative meta-analysis impossible, but permits us to develop a deductive framework for identifying the main mechanisms (and coupling thereof) through which climate extremes may act on the carbon cycle. We find that ecosystem responses can exceed the duration of the climate impacts via lagged effects on the carbon cycle. The expected regional impacts of future climate extremes will depend on changes in the probability and severity of their occurrence, on the compound effects and timing of different climate extremes, and on the vulnerability of each land-cover type modulated by management. Although processes and sensitivities differ among biomes, based on expert opinion, we expect forests to exhibit the largest net effect of extremes due to their large carbon pools and fluxes, potentially large indirect and lagged impacts, and long recovery time to regain previous stocks. At the global scale, we presume that droughts have the strongest and most widespread effects on terrestrial carbon cycling. Comparing impacts of climate extremes identified via remote sensing vs. ground-based observational case studies reveals that many regions in the (sub-)tropics are understudied. Hence, regional investigations are needed to allow a global upscaling of the impacts of climate extremes on global carbon-climate feedbacks.
KW  - carbon cycle
KW  - climate change
KW  - climate extremes
KW  - climate variability
KW  - disturbance
KW  - terrestrial ecosystems
Y1  - 2015
U6  - https://doi.org/10.1111/gcb.12916
SN  - 1354-1013
SN  - 1365-2486
VL  - 21
IS  - 8
SP  - 2861
EP  - 2880
PB  - Wiley-Blackwell
CY  - Hoboken
ER  -