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Title: Record-breaking statistics detect islands of cooling in a sea of warming
Abstract. Record-breaking statistics are combined here with ageographic mode of exploration to introduce a record-breaking map. Weexamine time series of sea surface temperature (SST) values and show thathigh SST records have been broken far more frequently than the expected rate for a trend-free random variable (TFRV) over the vast majority of oceans (83 % of the grid cells). This, together with the asymmetry between highand low records and their deviation from a TFRV, indicates SST warming overmost oceans, obtained using a distribution-independent, robust, andsimple-to-use method. The spatial patterns of this warming are coherent andreveal islands of cooling, such as the “cold blob” in the North Atlantic and a surprising elliptical area in the Southern Ocean, near the Ross Sea gyre, not previously reported. The method was also applied to evaluate a global climate model (GCM), which reproduced the observed records during the study period. The distribution of records from the GCM pre-industrial (PI) controlrun samples was similar to the one from a TFRV, suggesting that thecontribution of a suitably constrained internal variability to the observedrecord-breaking trends is negligible. Future forecasts show striking SSTtrends, with even more frequent high records and less frequent low records.  more » « less
Award ID(s):
1639868
PAR ID:
10396887
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Atmospheric Chemistry and Physics
Volume:
22
Issue:
24
ISSN:
1680-7324
Page Range / eLocation ID:
16111 to 16122
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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