Connecting North Atlantic SST Variability to European Heat Events over the Past Decades
The occurrence of European heat events has increased during the last two decades. European heat events are responsible for social, economic and environmental damage and are projected to increase in magnitude, frequency and duration under global warming, strengthening the interest about the contribut...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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Stockholm University Press
2023-11-01
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| Series: | Tellus: Series A, Dynamic Meteorology and Oceanography |
| Subjects: | |
| Online Access: | https://account.a.tellusjournals.se/index.php/su-j-tadmo/article/view/3235 |
| _version_ | 1797382740230799360 |
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| author | Julian Krüger Joakim Kjellsson Robin Pilch Kedzierski Martin Claus |
| author_facet | Julian Krüger Joakim Kjellsson Robin Pilch Kedzierski Martin Claus |
| author_sort | Julian Krüger |
| collection | DOAJ |
| description | The occurrence of European heat events has increased during the last two decades. European heat events are responsible for social, economic and environmental damage and are projected to increase in magnitude, frequency and duration under global warming, strengthening the interest about the contribution of different mechanisms. Using the ERA5 reanalysis product, we go beyond case studies relating European heat events with cold North Atlantic sea surface temperatures (SSTs), and perform a systematic approach with a composite analysis to investigate the link between North Atlantic SSTs in a domain south of Greenland and the 2m air temperature (T2m) over central Europe. Composites of different North Atlantic SST states show that events with a negative tendency of North Atlantic SSTs are often followed by positive European T2m anomalies during summers when the North Atlantic SSTs are persistently low for several months. Enhanced lower–tropospheric baroclinicity in the North Atlantic is followed during these events by a slantwise ascent and an enhanced upper–tropospheric waveguide, promoting a downstream development of an European ridge. A combination of a wave number 3 pattern and regionally confined Rossby wave activity contribute to a trough–ridge pattern in the North Atlantic–European sector. A composite of European heat events further confirms the lagged statistical relationship between cold North Atlantic SSTs with a negative tendency and positive European T2m anomalies. A negative tendency of North Atlantic SSTs precedes 15 of 18 European heat events, and cold North Atlantic SST conditions are present during 14 of 18 European heat events. |
| first_indexed | 2024-03-08T21:10:50Z |
| format | Article |
| id | doaj.art-dc225187b60240e9b991467d9dcbc688 |
| institution | Directory Open Access Journal |
| issn | 1600-0870 |
| language | English |
| last_indexed | 2024-03-08T21:10:50Z |
| publishDate | 2023-11-01 |
| publisher | Stockholm University Press |
| record_format | Article |
| series | Tellus: Series A, Dynamic Meteorology and Oceanography |
| spelling | doaj.art-dc225187b60240e9b991467d9dcbc6882023-12-22T06:43:25ZengStockholm University PressTellus: Series A, Dynamic Meteorology and Oceanography1600-08702023-11-01751358–374358–37410.16993/tellusa.32353202Connecting North Atlantic SST Variability to European Heat Events over the Past DecadesJulian Krüger0https://orcid.org/0000-0002-0135-1983Joakim Kjellsson1https://orcid.org/0000-0002-6405-5276Robin Pilch Kedzierski2https://orcid.org/0000-0003-3349-2454Martin Claus3https://orcid.org/0000-0002-7525-5134GEOMAR Helmholtz Centre for Ocean Research, Kiel; Christian–Albrechts–University, KielChristian–Albrechts–University, KielGEOMAR Helmholtz Centre for Ocean Research, KielGEOMAR Helmholtz Centre for Ocean Research, Kiel; Christian–Albrechts–University, KielThe occurrence of European heat events has increased during the last two decades. European heat events are responsible for social, economic and environmental damage and are projected to increase in magnitude, frequency and duration under global warming, strengthening the interest about the contribution of different mechanisms. Using the ERA5 reanalysis product, we go beyond case studies relating European heat events with cold North Atlantic sea surface temperatures (SSTs), and perform a systematic approach with a composite analysis to investigate the link between North Atlantic SSTs in a domain south of Greenland and the 2m air temperature (T2m) over central Europe. Composites of different North Atlantic SST states show that events with a negative tendency of North Atlantic SSTs are often followed by positive European T2m anomalies during summers when the North Atlantic SSTs are persistently low for several months. Enhanced lower–tropospheric baroclinicity in the North Atlantic is followed during these events by a slantwise ascent and an enhanced upper–tropospheric waveguide, promoting a downstream development of an European ridge. A combination of a wave number 3 pattern and regionally confined Rossby wave activity contribute to a trough–ridge pattern in the North Atlantic–European sector. A composite of European heat events further confirms the lagged statistical relationship between cold North Atlantic SSTs with a negative tendency and positive European T2m anomalies. A negative tendency of North Atlantic SSTs precedes 15 of 18 European heat events, and cold North Atlantic SST conditions are present during 14 of 18 European heat events.https://account.a.tellusjournals.se/index.php/su-j-tadmo/article/view/3235north atlantic ssteuropean heat eventstrough–ridge patternthermodynamical mechanismsplanetary wavesrossby wave packets |
| spellingShingle | Julian Krüger Joakim Kjellsson Robin Pilch Kedzierski Martin Claus Connecting North Atlantic SST Variability to European Heat Events over the Past Decades Tellus: Series A, Dynamic Meteorology and Oceanography north atlantic sst european heat events trough–ridge pattern thermodynamical mechanisms planetary waves rossby wave packets |
| title | Connecting North Atlantic SST Variability to European Heat Events over the Past Decades |
| title_full | Connecting North Atlantic SST Variability to European Heat Events over the Past Decades |
| title_fullStr | Connecting North Atlantic SST Variability to European Heat Events over the Past Decades |
| title_full_unstemmed | Connecting North Atlantic SST Variability to European Heat Events over the Past Decades |
| title_short | Connecting North Atlantic SST Variability to European Heat Events over the Past Decades |
| title_sort | connecting north atlantic sst variability to european heat events over the past decades |
| topic | north atlantic sst european heat events trough–ridge pattern thermodynamical mechanisms planetary waves rossby wave packets |
| url | https://account.a.tellusjournals.se/index.php/su-j-tadmo/article/view/3235 |
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