Sea level extremes and compounding marine heatwaves in coastal Indonesia

• DOI: 10.1038/s41467-022-34003-3
• Publication Date: 2022-10-27T15:22:48Z
• Authors: Weiqing Han; Lei Zhang; Gerald A. Meehl; Shoichiro Kido; Tomoki Tozuka; Yuanlong Li; Michael J. McPhaden; Aixue Hu; Anny Cazenave; Nan Rosenbloom; Gary Strand; B. Jason West; Wen Xing
• Keywords: Compounding; Marine Biology

Abstract Low-lying island nations like Indonesia are vulnerable to sea level Height EXtremes (HEXs). When compounded by marine heatwaves, HEXs have larger ecological and societal impact. Here we combine observations with model simulations, investigate the Compound Height-Heat Extremes (CHHEXs) along Indian Ocean coast of in recent decades. We find that anthropogenic rise combined decadal climate variability causes increased occurrence during 2010–2017. Both CHHEXs driven equatorial westerly longshore northwesterly wind anomalies. For most HEXs, which occur December-March, downwelling favorable northwest monsoon winds enhanced but vertical mixing limits surface warming. CHHEXs, anomalies associated a negative Dipole (IOD) co-occurring La Niña weaken southeasterlies cooling from coastal upwelling May-June November-December. Our findings emphasize important interplay between warming affecting regional extremes.