Attribution of the role of climate change in the forest fires in Sweden
2018

Krikken, Folmer; Lehner, Flavio; Haustein, Karsten; Drobyshev, Igor; Oldenborgh, Geert Jan van

doi:10.5194/nhess-2019-206

Cited by 24 publications

(27 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The FWI has been used to quantify fire conditions in previous studies using CESM simulations 10,16 , and details for its calculation are described extensively by Wagner 24 and Dowdy et al 28 . There are some discrepancies between FWI for CESM-LE over 1980-2018 compared to ERA-Interim reanalysis, used in lieu of observations.…”

Section: Methodsmentioning

confidence: 99%

“…In fact, for two-thirds of the global burnable area, extreme fire-weather conditions are expected to become the new normal by 2100 15 . The magnitude of these changes will of course depend on the future emissions scenario, but are a common feature even of lowemissions projections; for instance, in Sweden, a future global warming scenario of 2°C doubles the risk of extreme fire weather 16 .…”

mentioning

confidence: 99%

See 1 more Smart Citation

Human-driven greenhouse gas and aerosol emissions cause distinct regional impacts on extreme fire weather

et al. 2021

Self Cite

View full text Add to dashboard Cite

Attribution studies have identified a robust anthropogenic fingerprint in increased 21st century wildfire risk. However, the risks associated with individual aspects of anthropogenic aerosol and greenhouse gases (GHG) emissions, biomass burning and land use/land cover change remain unknown. Here, we use new climate model large ensembles isolating these influences to show that GHG-driven increases in extreme fire weather conditions have been balanced by aerosol-driven cooling throughout the 20th century. This compensation is projected to disappear due to future reductions in aerosol emissions, causing unprecedented increases in extreme fire weather risk in the 21st century as GHGs continue to rise. Changes to temperature and relative humidity drive the largest shifts in extreme fire weather conditions; this is particularly apparent over the Amazon, where GHGs cause a seven-fold increase by 2080. Our results allow increased understanding of the interacting roles of anthropogenic stressors in altering the regional expression of future wildfire risk.

show abstract

Section: Methodsmentioning

confidence: 99%

mentioning

confidence: 99%

Human-driven greenhouse gas and aerosol emissions cause distinct regional impacts on extreme fire weather

et al. 2021

Self Cite

View full text Add to dashboard Cite

show abstract

“…In Australia the Forest Fire Danger Index (FFDI McArthur,55 conduct an attribution study on the Fire Weather Index (FWI) and the Monthly Severity Rating (MSR). These three attribution studies follow the same protocol used in previous assessments (Heat waves: Kew et al (2019); low precipitation: Otto et al (2018b); Fire Weather Index: Krikken et al (2019). We continue the analysis with a discussion of other large scale drivers, such as El Niño Southern Oscillation (ENSO), the Indian Ocean Dipole (IOD) or the Southern Annular Mode (SAM).…”

mentioning

confidence: 99%

Attribution of the Australian bushfire risk to anthropogenic climate change

Oldenborgh¹,

Krikken²,

Lewis³

et al. 2020

Preprint

Self Cite

116

View full text Add to dashboard Cite

Disastrous bushfires during the last months of 2019 and January 2020 affected Australia, raising the question to what extent the risk of these fires was exacerbated by anthropogenic climate change. To answer the question for southeastern Australia, where fires were particularly severe, affecting people and ecosystems, we use a physically-based index of fire weather, the Fire Weather Index, long-term observations of heat and drought, and eleven large ensembles of state-of-the-art climate models. In agreement with previous analyses we find that heat extremes have become more likely by at least a factor 5 two due to the long-term warming trend. However, current climate models overestimate variability and tend to underestimate the long-term trend in these extremes, so the true change in the likelihood of extreme heat could be larger. We do not find an attributable trend in either extreme annual drought or the driest month of the fire season September-February. The observations, however, show a weak drying trend in the annual mean. Finally, we find large trends in the Fire Weather Index in the ERA5 reanalysis, and a smaller but significant increase by at least 30% in the models. The trend is mainly driven by the increase 10 of temperature extremes and hence also likely underestimated. For the 2019/20 season more than half of the July-December drought was driven by record excursions of the Indian Ocean dipole and Southern Annular Mode. These factors are included in the analysis. The study reveals the complexity of the 2019/20 bushfire event, with some, but not all drivers showing an imprint of anthropogenic climate change.

show abstract

“…The sustained period with warm conditions, in connection with little precipitation, led to a prolonged drought. The hot and dry conditions in summer 2018 in Sweden were associated with severe consequences for people and the environment including: health problems and excessive mortality rate among people (Åström et al 2019); water shortages with adverse implications for arable land and pastures (Buras et al 2019) including lack of forage; unusual large areas affected by forest fires (Krikken et al 2019). Also, other environmental impacts such as excessive fluxes of carbon dioxide and methane due to extremely warm conditions in shallow parts of the Baltic Sea were observed (Humborg et al 2019).…”

Section: Introductionmentioning

confidence: 99%

The extremely warm summer 2018 in Sweden – set in a historical context

Wilcke¹,

Kjellström²,

Lin³

et al. 2020

Preprint

View full text Add to dashboard Cite

Abstract. Two long-lasting high pressure systems in summer 2018 lead to long lasting heat waves over Scandinavia and other parts of Europe and an extended summer period with devastating impacts on agriculture, infrastructure and human life. We use five climate model ensembles and the unique 263 year long Stockholm temperature time series along with a composite 150 year long time series for whole Sweden to set the latest heat-wave in summer 2018 in historical perspective. With 263 years we are able to grasp the pre-industrial time well and see a clear upward trend in temperature itself as well as heat wave indicators. With five climate model ensembles providing 20 580 simulated summers representing the latest 70 years, we analyse the likelihood of such a heat event and how unusual the 2018 Swedish summer actually was. We find that conditions as those observed in summer 2018 show up in all climate model ensembles. An exception is the monthly mean temperature for May for which 2018 was warmer than any member in one of the five climate model ensembles. However, even if the ensembles generally hold individual years like 2018, the comparison shows that such conditions are rare. For the indices assessed here, anomalies such as observed in 2018 occur maximally in 5 % of the ensemble members, sometimes even in less than 1 %. For all indices evaluated we find that probabilities of a summer like in 2018 have increased from relatively low values for the one ensemble extending back to 1861–90 and for all five ensembles including 1951–80 to the most recent decades (1989–2018). An implication is that anthropogenic climate change has strongly increased the probability of a warm summer such as the one observed 2018 to occur in Sweden. Despite this, we still find such summers also in the pre-industrial climate, however, with a lower probability.

show abstract

Attribution of the role of climate change in the forest fires in Sweden 2018

Cited by 24 publications

References 22 publications

Human-driven greenhouse gas and aerosol emissions cause distinct regional impacts on extreme fire weather

Human-driven greenhouse gas and aerosol emissions cause distinct regional impacts on extreme fire weather

Attribution of the Australian bushfire risk to anthropogenic climate change

The extremely warm summer 2018 in Sweden – set in a historical context

Contact Info

Product

Resources

About