Combining the Monthly Drought Code and Paleoecological Data to Assess Holocene Climate Impact on Mediterranean Fire Regime
Currently, indexes from the Fire Weather Index System (FWI) are used to predict the daily fire hazard, but there is no reliable index available in the Mediterranean region to be compared with paleofire records and check for their long-term reliability. In order to assess the past fire hazard and the...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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MDPI AG
2020-04-01
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| Series: | Fire |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2571-6255/3/2/8 |
| _version_ | 1797571149320683520 |
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| author | Marion Lestienne Christelle Hély Thomas Curt Isabelle Jouffroy-Bapicot Boris Vannière |
| author_facet | Marion Lestienne Christelle Hély Thomas Curt Isabelle Jouffroy-Bapicot Boris Vannière |
| author_sort | Marion Lestienne |
| collection | DOAJ |
| description | Currently, indexes from the Fire Weather Index System (FWI) are used to predict the daily fire hazard, but there is no reliable index available in the Mediterranean region to be compared with paleofire records and check for their long-term reliability. In order to assess the past fire hazard and the fire-season length, based on data availability and requirements for fire index computation, we first chose and tested the efficiency of the Drought Code (DC) in Corsica (the main French Mediterranean fire-prone region) over the current period (1979–2016). We then used DC as a benchmark to assess the efficiency of the Monthly Drought Code (MDC) and used it to assess the Fire-Season Length (FSL), which were both used to characterize the fire hazard. Finally, we computed the Holocene MDC and FSL based on the HadCM3B-M1 climate model (three dimensional, fully dynamic, coupled atmosphere-ocean global climate model without flux adjustment) datasets and compared both index trends with those from proxies of paleofire, vegetation, and land use retrieved from sedimentary records in three Corsican lakes (Bastani, Nino, and Creno). Our strategy was to (i) assess fire hazard without the constraint of the daily weather-data requirement, (ii) reconstruct Holocene fire hazard from a climate perspective, and (iii) discuss the role of climate and human fire drivers based on the MDC-Paleofire proxy comparisons. Using both the Prométhée fire database and the ERA-Interim climate database over Corsica for the current period, we showed that DC values higher than 405 units efficiently discriminated fire-days from no-fire-days. The equivalent threshold value from MDC was set at 300 units. MDC and FSL indexes calculated for each of the past 11 millennia Before Present (11 ka BP) showed high values before 7 ka BP (above 300 units for MDC) and then lower values for the mid- to late Holocene (below 300 units for MDC). Climate appeared as a key driver to predict fire occurrences, promoting fires between 11 and 8 ka BP when summers were warmer than the current ones and reducing fire hazard after 7–6 ka BP due to wetter conditions. Since 5 ka BP, humans have taken control of the fire regime through agro-pastoralism, favoring large and/or frequent events despite less fire-prone climate conditions. The current fire hazard and fire-season length computed over the last few decades (1979–2016) both reported values that were respectively higher and longer than those assessed for the previous six millennia at least and comparable for those before 7 ka BP. For the next decades, due to climate warming associated with land abandonment (fuel accumulation) and the increase in human-related sources of ignition, we can expect an increase in fire hazard and larger fire events. |
| first_indexed | 2024-03-10T20:35:21Z |
| format | Article |
| id | doaj.art-c213bbece354447a8290cf60d5df3bfc |
| institution | Directory Open Access Journal |
| issn | 2571-6255 |
| language | English |
| last_indexed | 2024-03-10T20:35:21Z |
| publishDate | 2020-04-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Fire |
| spelling | doaj.art-c213bbece354447a8290cf60d5df3bfc2023-11-19T21:04:46ZengMDPI AGFire2571-62552020-04-0132810.3390/fire3020008Combining the Monthly Drought Code and Paleoecological Data to Assess Holocene Climate Impact on Mediterranean Fire RegimeMarion Lestienne0Christelle Hély1Thomas Curt2Isabelle Jouffroy-Bapicot3Boris Vannière4Chrono-Environnement, CNRS, Université Bourgogne Franche-Comté, 25000 Besançon, FranceThe Institute of Evolution Sciences of Montpellier, Université Montpellier, CNRS, EPHE, IRD, 34090 Montpellier, FranceNational Research Institute of Science and Technology for Environment and Agriculture, Mediterranean Ecosystems and Risks, 13100 Aix-en-Provence, FranceChrono-Environnement, CNRS, Université Bourgogne Franche-Comté, 25000 Besançon, FranceChrono-Environnement, CNRS, Université Bourgogne Franche-Comté, 25000 Besançon, FranceCurrently, indexes from the Fire Weather Index System (FWI) are used to predict the daily fire hazard, but there is no reliable index available in the Mediterranean region to be compared with paleofire records and check for their long-term reliability. In order to assess the past fire hazard and the fire-season length, based on data availability and requirements for fire index computation, we first chose and tested the efficiency of the Drought Code (DC) in Corsica (the main French Mediterranean fire-prone region) over the current period (1979–2016). We then used DC as a benchmark to assess the efficiency of the Monthly Drought Code (MDC) and used it to assess the Fire-Season Length (FSL), which were both used to characterize the fire hazard. Finally, we computed the Holocene MDC and FSL based on the HadCM3B-M1 climate model (three dimensional, fully dynamic, coupled atmosphere-ocean global climate model without flux adjustment) datasets and compared both index trends with those from proxies of paleofire, vegetation, and land use retrieved from sedimentary records in three Corsican lakes (Bastani, Nino, and Creno). Our strategy was to (i) assess fire hazard without the constraint of the daily weather-data requirement, (ii) reconstruct Holocene fire hazard from a climate perspective, and (iii) discuss the role of climate and human fire drivers based on the MDC-Paleofire proxy comparisons. Using both the Prométhée fire database and the ERA-Interim climate database over Corsica for the current period, we showed that DC values higher than 405 units efficiently discriminated fire-days from no-fire-days. The equivalent threshold value from MDC was set at 300 units. MDC and FSL indexes calculated for each of the past 11 millennia Before Present (11 ka BP) showed high values before 7 ka BP (above 300 units for MDC) and then lower values for the mid- to late Holocene (below 300 units for MDC). Climate appeared as a key driver to predict fire occurrences, promoting fires between 11 and 8 ka BP when summers were warmer than the current ones and reducing fire hazard after 7–6 ka BP due to wetter conditions. Since 5 ka BP, humans have taken control of the fire regime through agro-pastoralism, favoring large and/or frequent events despite less fire-prone climate conditions. The current fire hazard and fire-season length computed over the last few decades (1979–2016) both reported values that were respectively higher and longer than those assessed for the previous six millennia at least and comparable for those before 7 ka BP. For the next decades, due to climate warming associated with land abandonment (fuel accumulation) and the increase in human-related sources of ignition, we can expect an increase in fire hazard and larger fire events.https://www.mdpi.com/2571-6255/3/2/8fire hazardfire weather indexdrought codefire-seasonmodellingpaleofire |
| spellingShingle | Marion Lestienne Christelle Hély Thomas Curt Isabelle Jouffroy-Bapicot Boris Vannière Combining the Monthly Drought Code and Paleoecological Data to Assess Holocene Climate Impact on Mediterranean Fire Regime Fire fire hazard fire weather index drought code fire-season modelling paleofire |
| title | Combining the Monthly Drought Code and Paleoecological Data to Assess Holocene Climate Impact on Mediterranean Fire Regime |
| title_full | Combining the Monthly Drought Code and Paleoecological Data to Assess Holocene Climate Impact on Mediterranean Fire Regime |
| title_fullStr | Combining the Monthly Drought Code and Paleoecological Data to Assess Holocene Climate Impact on Mediterranean Fire Regime |
| title_full_unstemmed | Combining the Monthly Drought Code and Paleoecological Data to Assess Holocene Climate Impact on Mediterranean Fire Regime |
| title_short | Combining the Monthly Drought Code and Paleoecological Data to Assess Holocene Climate Impact on Mediterranean Fire Regime |
| title_sort | combining the monthly drought code and paleoecological data to assess holocene climate impact on mediterranean fire regime |
| topic | fire hazard fire weather index drought code fire-season modelling paleofire |
| url | https://www.mdpi.com/2571-6255/3/2/8 |
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