Table 2.
Characteristics of strong MHWs identified in the literature (1982–2016)
| Metrics | ||||||
|---|---|---|---|---|---|---|
| Typology | Case study | Marine Heatwaves (Refs. in SI) | Start date (>98%) | End date (<98%) | Max intensity [°C (Date)] | Max area >98% [Mkm2 (Date)] |
| EBC | Benguela |
1982/83 1984 1995 2001 |
21/12/1982 8/3/1984 5/2/1995 21/3/1995 11/4/1995 27/4/2001 |
31/1/1983 12/3/1984 19/2/1995 1/4/1995 21/4/1995 20/5/2001 |
4.8 (22/1/1983) 4.6(9/3/1984) 4.7(7/2/1995) 5.7(22/3/1995) 6.7(16/4/1995) 5.3 (14/5/2001) |
1.4 (24/1/1983) 0.13(9/3/1984) 0.2 (17/2/1995) 0.3 (27/3/1995) 0.6 (17/4/1995) 0.7 (16/5/2001) |
| Leeuwin |
1989 1999/2000 2011 2012 2012/13 |
– – 8/2/2011 20/1/12 2/1/2013 |
– – 23/3/2011 29/1/12 10/1/2013 |
– – 6.8(26/2/2011) 5.1(28/1/11) 4.0 (2/1/2013) |
– – 0.95(4/3/2011) 0.3 (17/1/11) 0.24 (5/1/2013) |
|
| Baja California |
1982/83 1997 2015/16 |
10/2/1983 14/11/1997 30/12/1997 10/2/1998 1/7/2015 |
5/3/1984 11/12/1997 14/1/1998 20/2/1998 2/1/2016 |
4.0(23/2/1983) 4.6(26/11/1997) 4.2(31/12/1997) 3.5(19/2/1998) 6.4(12/9/2015) |
0.12(24/2/1983) 0.37(6/12/1997) 0.39 (3/1/1998) 0.17(16/2/1998) 21.2(2/11/2015) |
|
| Iberian/Canary | – | – | – | – | – | |
| Humboldt/Peru |
1982 1983 1997/98 |
23/8/1982 14/10/1982 26/11/1982 5/1/1983 30/5/1997 9/7/1997 3/9/1997 24/9/1997 25/11/1997 |
7/10/1982 18/11/1982 14/12/1982 24/7/1983 18/6/1997 25/8/1997 17/9/1997 17/11/1997 28/12/1997 |
4.2(10/9/1982) 3.9(16/11/1982) 5.5(11/12/1982) 9.6 (6/5/1983) 4.1(2/6/1997) 6.2(21/7/1997) 6.5(7/9/1997) 6.2(7/11/1997) 6.9(28/11/1997) |
2.1(29/9/1982) 0.25(16/11/1982) 1.0(9/12/1982) 4.4 (24/6/1983) 5.4(12/6/1997) 4.7(18/8/1997) 8.1 (4/9/1997) 7.0(26/9/1997) 4.1(5/12/1997) |
|
| WBC | East Australian Current Extension | 2016 | 7/12/2015 | 12/4/2016 | 7.5(8.2.2016) | 0.7(6/3/2016) |
| Agulhas Retroflection | 1985 | 29/11/1985 | 5/12/1985 | 0.2(2/12/1985) | 5.7(29/11/1985) | |
| Tropics | Great Barrier Reef/Coral Sea |
1998 2001/02 2015/16 |
9/2/1998 30/12/2001 28/2/2016 |
18/3/1998 15/1/2002 4/4/2016 |
3.4(4/3/1998) 3.3 (6/1/2002) 4.0 (15/3/2016) |
0.14 (5/3/1998) 0.5(8/1/2002) 2.6 (12/3/2016) |
| Seychelles Is. | 1997/98 |
14/1/1998 14/2/1998 |
3/2/1998 22/2/1998 |
3.7(25/1/1998) 3.4(21/2/1998) |
0.4(18/1/1998) 0.9(18/2/1998) |
|
| Galápagos Is. (Eq. Pac) |
1982/83 1987 1992 1997/98 |
5/5/1983 – – 14/7/1997 |
31/7/1983 3/6/1998 |
9.56(6/5/1983) 6.9(28/11/1997) |
4.7(5/6/1983) 11(9/11/1997) |
|
| Bay of Bengal | 2010 | 4/5/2010 | 6/6/2010 | 3.4(15/5/2010) | 1.1(14/5/2010) | |
| Caribbean Sea |
1982/83 1987/88 1989/90 |
– – – |
– – – |
– – – |
– – – |
|
| MHL | Mediterranean Sea |
1999 2003 |
– 6/9/2003 8/8/2003 |
– 16/7/2003 4/9/2003 |
– 5.5(14/6/2003) 4.6 (29/8/2003) |
– 0.5(16/6/2003) 1.2(23/8/2003) |
| Bering Sea | 1997 | 31/5/1997 | 27/6/1997 | 5.1(12/6/1997) | 0.05(4/6/1997) | |
| Northwest Atlantic Ocean | 2012 |
18/3/2012 17/4/2012 19/5/2012 21/6/2012 19/9/2012 31/10/2012 |
25/3/2012 28/4/2012 31/5/2012 10/9/2012 13/10/2012 27/11/2012 |
10.3 (23/3/2012) 5.4(17/4/2012) 7.5(23/5/2012) 9.2(6.7/2012) 6.1 (8/10/2012) 8.1(27/11/2012) |
0.3(22/3/2012) 0.3(25/4/2012) 0.2(26/5/2012) 0.1(1/8/2012) 0.3(8/10/2012) 0.2(3/11/2012) |
|
| Northeast Pacific Ocean | 2013–2015 |
14/11/2013 28/7/2014 |
30/6/2014 31/8/2015 |
4.8(3/6/2014) 6.7(28/6/2015) |
4.5(17/1/2014) 11.7(15/2/2015) |
|
| South Central Pacific Ocean | 2009/10 | 9/11/2009 | 2/3/2010 | 6.0(24//12/2009) | 3.9(25/12/2009) | |
MHWs were identified using the quantitative definition6 applied here to derive metrics (but based on a 98th-percentile threshold). Those MHWs identified in the literature that have a dash ‘–’ did not meet the 98th percentile criteria although identified in the literature with the corresponding references (see Supplementary Table 2). Further, some of the closely separated MHW events defined here (e.g. Humboldt/Peru Current region in 1982, 1983 and 1997/98; and the northeast Pacific region in 2013/14 and 2014/15) would be considered a continuous MHW if a weaker threshold was used