TY - JOUR
T1 - The heat wave of October 2020 in central South America
AU - Marengo, Jose A.
AU - Ambrizzi, Tercio
AU - Barreto, Naurinete
AU - Cunha, Ana Paula
AU - Ramos, Andrea M.
AU - Skansi, Milagros
AU - Molina Carpio, Jorge
AU - Salinas, Roberto
N1 - Publisher Copyright:
© 2021 Royal Meteorological Society
PY - 2022/3/30
Y1 - 2022/3/30
N2 - During September–November 2020, the meteorological services of Brazil, Argentina, Peru, Paraguay, and Bolivia reported record-high maximum temperatures in several warm spells during this season. Positive and significant trends in heat wave frequency, intensity, and duration have been recorded since the 1980s, particularly in large cities. In this study, a heat wave is defined as a period in which both daily maximum and minimum air temperatures exceed the corresponding climatological 90th percentile for three or more consecutive days during September–November 2020. In this period, an intense heat wave during the first half of October and two heat waves events in November resulted in record-breaking daily maximum temperatures in several locations in central South America. Places experienced temperature of about 10°C above normal, and some locations reported maximum temperatures above 40°C for several days in a row. Because its intensity and geographical extension, affecting central South America from southern Peruvian Amazon to southeastern Brazil, the heat wave of September 23–October 15 was selected as a case study. This intense heat wave was due a persistent atmospheric blocking located starting in late September and lasting until middle October 2020, a continuous presence of a warm air mass for several consecutive days contributed to pronounced positive temperature anomalies, possibly reinforced by extremely low soil moisture. This makes it easier for these high-pressure systems to generate extreme heat waves because more of the sun's energy is going into heating the atmosphere rather than evaporating non-existent water in the soil. This heat wave aggravated the drought over the Pantanal and other regions in October 2020, increasing fires and impacts on natural and human systems, representing a severe drought-heat compound event. This vicious cycle of drought and extreme heat is of the kind expected under a warming climate.
AB - During September–November 2020, the meteorological services of Brazil, Argentina, Peru, Paraguay, and Bolivia reported record-high maximum temperatures in several warm spells during this season. Positive and significant trends in heat wave frequency, intensity, and duration have been recorded since the 1980s, particularly in large cities. In this study, a heat wave is defined as a period in which both daily maximum and minimum air temperatures exceed the corresponding climatological 90th percentile for three or more consecutive days during September–November 2020. In this period, an intense heat wave during the first half of October and two heat waves events in November resulted in record-breaking daily maximum temperatures in several locations in central South America. Places experienced temperature of about 10°C above normal, and some locations reported maximum temperatures above 40°C for several days in a row. Because its intensity and geographical extension, affecting central South America from southern Peruvian Amazon to southeastern Brazil, the heat wave of September 23–October 15 was selected as a case study. This intense heat wave was due a persistent atmospheric blocking located starting in late September and lasting until middle October 2020, a continuous presence of a warm air mass for several consecutive days contributed to pronounced positive temperature anomalies, possibly reinforced by extremely low soil moisture. This makes it easier for these high-pressure systems to generate extreme heat waves because more of the sun's energy is going into heating the atmosphere rather than evaporating non-existent water in the soil. This heat wave aggravated the drought over the Pantanal and other regions in October 2020, increasing fires and impacts on natural and human systems, representing a severe drought-heat compound event. This vicious cycle of drought and extreme heat is of the kind expected under a warming climate.
KW - compound event
KW - drought
KW - heat wave
KW - maximum temperature
UR - http://www.scopus.com/inward/record.url?scp=85114429372&partnerID=8YFLogxK
U2 - 10.1002/joc.7365
DO - 10.1002/joc.7365
M3 - Artículo
AN - SCOPUS:85114429372
VL - 42
SP - 2281
EP - 2298
JO - International Journal of Climatology
JF - International Journal of Climatology
SN - 0899-8418
IS - 4
ER -