Tuesday, October 22, 2013

New paper finds European fire activity is at lowest levels of past 10,000 years

A new paper published in Quaternary Science Reviews reconstructs fire activity in Central-Eastern Europe over the past 12,000 years and finds modern fire activity is near the lowest levels of the past 10,000 years. The paper adds to many others finding a long-term decrease in fire activity, despite claims of climate alarmists. 

The paper also shows that reconstructed early and late summer temperatures in Central-Eastern Europe have both declined over the past ~10,000 years.

The US is currently experiencing the lowest fire activity in three decades, and the current New South Wales fires have nothing to do with CO2

Reconstructed fire activity shown in top graph is at the lowest levels of the past 10,000 years. Reconstructed early and late summer temperatures in Central-Eastern Europe have declined over the past ~10,000 years, shown in 2nd graph from bottom. Horizontal axis is thousands of years before the present.

12,000-Years of fire regime drivers in the lowlands of Transylvania (Central-Eastern Europe): a data-model approach

  • a Senckenberg Research Institute and Natural History Museum, Senckenberganlage 25, 60325 Frankfurt am Main, Germany
  • b Biodiversity and Climate Research Centre (BiK-F), Senckenberganlage 25, 60325 Frankfurt am Main, Germany
  • c CNRS, UMR 6249 Chrono-Environnement, Université de Franche-Comté, 16 route de Gray, 25030 Besançon Cedex, France
  • d Centre for Archaeological Sciences, University of Leuven, Celestijnenlaan 200E, Bus 2408, 3001 Leuven, Belgium
  • e School of Environment and Life Sciences, University of Salford, Salford M5 4WT, UK
  • f Goethe University, Department of Physical Geography, Altenhöferallee 1, 60438 Frankfurt am Main, Germany

Highlights

First multi-proxy record and climate modelling of fire regime in CE Europe.
Strong influence of early summer temperature and moisture content on fire activity.
High sensitivity of fire activity to the short-lived climate events.
Frequent fires associated with open woodlands, whereas the decline in fire risk favoured woodland development.
Synergic influence of natural and human factors on fire frequency from 3300 BP.

Abstract

The usefulness of sedimentary charcoal records to document centennial to millennial scale trends in aspects of fire regimes (frequency, severity) is widely acknowledged, yet the long-term variability in these regimes is poorly understood. Here, we use a high-resolution, multi-proxy analysis of a lacustrine sequence located in the lowlands of Transylvania (NW Romania), alongside global climate simulations in order to disentangle the drivers of fire regimes in this dry climatic region of Central-Eastern Europe. Periods of greater fire activity and frequency occurred between 10,700 and 7100 cal yr BP (mean Fire Interval = mFI 112 yr), and between 3300 and 700 cal yr BP (mFI 150 yr), whereas intervals of lower fire activity were recorded between 12,000 and 10,700 cal yr BP (mFI 217 yr), 7100 and 3300 cal yr BP (mFI 317 yr), and over last 700 years (no fire events detected). We found good correlations between simulated early summer (June, July) soil moisture content and near-surface air temperature with fire activity, particularly for the early to mid Holocene. A climate–fire relationship is further supported by local hydrological changes, i.e., lake level and runoff fluctuations. Fuel limitation, as a result of arid and strongly seasonal climatic conditions, led to low fire activity before 10,700 cal yr BP. However, fires were most frequent during climatically drier phases for the remaining, fuel-sufficient, part of the Holocene. Our results also suggest that the occurrence of more frequent fires in the early Holocene has kept woodlands open, promoted grassland abundance and sustained a more flammable ecosystem (mFI < 150 years) whereas the decline in fire risk under cooler and wetter climate conditions (mFI = 317 years) favoured woodland development. From 3300 cal yr BP, human impacts clearly were partly responsible for changes in fire activity, first increasing fire frequency and severity in periods with fire-favourable climatic conditions (halving the mFI from 300 years to about 150 years), then effectively suppressing fires over the last several centuries. Given the projected future temperature increase and moisture decline and the biomass accumulation due to the agricultural land abandonment in the region, natural fire frequency would be expected to return to <150 p="" years.="">

2 comments:

  1. The conclusions summarised in the Abstract do not appear to support your claims above.

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    Replies
    1. The "projected future temperature increase" is based upon highly flawed climate models that exaggerate warming. Every single one of the 73 IPCC AR5 climate models exaggerated warming.

      http://www.drroyspencer.com/wp-content/uploads/CMIP5-73-models-vs-obs-20N-20S-MT-5-yr-means1.png

      The models have been falsified at confidence levels of 90-95-98% over the past 15-20 years. Thus, all conclusions based upon these models are erroneous.

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