FN Archimer Export Format
PT J
TI Compound marine heatwaves and ocean acidity extremes
BT 
AF BURGER, Friedrich A.
   TERHAAR, Jens
   FROLICHER, Thomas L.
AS 1:1,2;2:1,2;3:1,2;
FF 1:;2:;3:;
C1 Climate and Environmental Physics, Physics Institute, University of Bern, Bern, Switzerland
   Oeschger Centre for Climate Change Research, University of Bern, Bern, Switzerland
C2 UNIV BERN, SWITZERLAND
   UNIV BERN, SWITZERLAND
IN DOAJ
TC 34
UR https://archimer.ifremer.fr/doc/00795/90658/96247.pdf
   https://archimer.ifremer.fr/doc/00795/90658/96248.pdf
   https://archimer.ifremer.fr/doc/00795/90658/96249.pdf
LA English
DT Article
CR OISO - OCÉAN INDIEN SERVICE D'OBSERVATION
DE ;Carbon cycle;Marine chemistry;Natural hazards;Physical oceanography
AB Compound MHW-OAX events, during which marine heatwaves (MHWs) co-occur with ocean acidity extreme (OAX) events, can have larger impacts on marine ecosystems than the individual extremes. Using monthly open-ocean observations over the period 1982-2019, we show that globally 1.8 in 100 months (or about one out of five present-day MHW months) are compound MHW-OAX event months under a present-day baseline, almost twice as many as expected for 90th percentile extreme event exceedances if MHWs and OAX events were statistically independent. Compound MHW-OAX events are most likely in the subtropics (2.7 in 100 months; 10 degrees-40 degrees latitude) and less likely in the equatorial Pacific and the mid-to-high latitudes (0.7 in 100 months; >40 degrees latitude). The likelihood pattern results from opposing effects of temperature and dissolved inorganic carbon on [H+]. The likelihood is higher where the positive effect on [H+] from increased temperatures during MHWs outweighs the negative effect on [H+] from co-occurring decreases in dissolved inorganic carbon. Daily model output from a large-ensemble simulation of an Earth system model is analyzed to assess changes in the MHW-OAX likelihood under climate change. The projected long-term mean warming and acidification trends have the largest effect on the number of MHW-OAX days per year, increasing it from 12 to 265 days per year at 2 degrees C global warming relative to a fixed pre-industrial baseline. Even when long-term trends are removed, an increase in [H+] variability leads to a 60% increase in the number of MHW-OAX days under 2 degrees C global warming. These projected increases may cause severe impacts on marine ecosystems. Compound extreme events in two or more oceanic ecosystem stressors are increasingly considered as a major concern for marine life. Here the authors present a first global analysis on compound marine heatwave and ocean acidity extreme events, identifying hotspots, drivers, and projecting future changes. 
PY 2022
PD AUG
SO Nature Communications
PU Nature Portfolio
VL 13
IS 1
UT 000841396400007
DI 10.1038/s41467-022-32120-7
ID 90658
ER

EF