@article{fdi:010097050,
  title = {{S}ensitivity of marine heatwaves metrics to {SST} products, focusing on the {T}ropical {P}acific},
  author = {{C}hevillard, {C}. and {L}e {G}endre, {R}. and {M}enk{\`e}s, {C}hristophe and {I}zumo, {T}akeshi and {P}agli, {B}astien and {V}an {W}ynsberge, {S}. and {C}ravatte, {S}ophie},
  editor = {},
  language = {{ENG}},
  abstract = {{M}arine heatwaves ({MHW}s) are increasingly studied in climate sciences for their ecological impacts, for which accurate real-time bulletins and forecasts are essential. {Y}et, methodological choices in their detection affect metric estimates, underlining the need to better assess these sensitivities. {T}his study provides a thorough assessment of the impact of sea surface temperature ({SST}) product choice on {MHW} statistics, focusing on the tropical {P}acific. {MHW} detection was performed on six daily gridded {SST} datasets: four widely used blended satellite observational products, one ocean reanalysis, and a multi-dataset ensemble mean computed from the four observational products. {S}ensitivity to {SST} products was evaluated for six {MHW} metrics ({MHW} days per year, number of events per year, duration, maximum intensity, cumulative intensity and onset rate) and for the degree heating weeks ({DHW}), a widely used index for coral bleaching risk. {I}nter-product comparisons revealed a significant dispersion among {MHW} metric estimates. {T}he reanalysis {GLORYS}12v1 detected fewer, longer and less intense {MHW}s while {OISST} detected more {MHW}s of shorter duration and higher intensity. likely related to the respectively weak and strong high-frequency {SST} variability (periods shorter than 2 weeks) of the two products. {T}he sensitivity analysis showed that the onset rate was the most sensitive metric to {SST} product choice and the maximum intensity the most robust one. {M}etrics uncertainties were quantified inside seven regions of the basin and were largest in the western {P}acific {W}arm {P}ool. {C}o-occurrence analyses of {MHW}s revealed that, over the basin, 10 % to 80 % of {MHW} days were detected simultaneously by all products, with the western {P}acific {W}arm {P}ool showing the lowest agreement (10 %-40 %). {F}iltering {MHW}s by size also revealed that the detection of large-scale {MHW}s (>5 degrees lon & times;5 degrees lat) was more consistent across products than smaller-scale ones. {F}inally, over the studied period, inter-product differences tended to decrease with time. {T}he {DHW} also revealed to be sensitive to {SST} products, with inter-product differences on {DHW} annual maximum reaching more than 1 degrees {C}weeks and percentages of bleaching alert days ({DHW} >= 4 degrees {C}weeks) in common across products reaching 70 % at most across much of the basin. {T}hese findings contribute to a better understanding of how {SST} product choice affects the characterization of {MHW}s and {DHW}, and their associated uncertainties.},
  keywords = {{PACIFIQUE} ; {ZONE} {TROPICALE}},
  booktitle = {},
  journal = {{O}cean {S}cience},
  volume = {22},
  numero = {2},
  pages = {1213--1236},
  ISSN = {1812-0784},
  year = {2026},
  DOI = {10.5194/os-22-1213-2026},
  URL = {https://www.documentation.ird.fr/hor/fdi:010097050},
}