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| Titel |
Wildfire in Northern Eurasia and climate change |
| VerfasserIn |
A. Shvidenko, D. Schepaschenko |
| Konferenz |
EGU General Assembly 2012
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 14 (2012) |
| Datensatznummer |
250065151
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| Zusammenfassung |
| The presentation considers dynamics of fire regimes in Northern Eurasia (limited to
territories of Russia) and their impacts on ecosystems and major global biogeochemical
cycles. Historically, fire regimes in different regions were defined by natural climate
variability, previous fire history and the level of direct human impact. The climate specifics
over the last three decades in Russia substantially impacted fire extent, frequency
and severity. Regular occurrence of mega(catastrophic) fires becomes a distinct
feature of current fire regimes. Megafires (e.g., 1998, 2003, 2008, 2010) lead to
degradation of ecosystems and the profound depletion of biodiversity, substantial
increase of emissions, create special atmospheric and seasonal weather over large
areas, cause considerable damage to the economy and infrastructure, as well as
adversely affect the living conditions and health of the population in the regions of fire
spread.
Based on a synthesis of remote sensing and ground data, the total area of wildfire in
Russia between 1998-2010 is assessed at 106.9 x 106 ha or 8.23 x 106 ha yr-1, varying from
4.2 (1999) up to 17.3 x 106 ha yr-1 (2003). The uncertainty of the assessment of burnt area
was estimated at ± 9%, and direct emissions of carbon at ± 23% (CI 0.9). As a rule,
~90% of the burnt area is located in Asian Russia, mainly in its southern half.
About two-thirds (65.1%) of the total burned area is situated on forest land, 18.9%
happened on agricultural land, 8.7% - on grass- and shrubland, and 7.3% - on wetland.
The total amount of fuel that was consumed between 1998-2010 was assessed at
1.57 x 109 t C, or 121.0 Tg C yr-1. Interannual variability of this value is high –
from 50 (2000) up to 231 Tg C yr-1 (2003) depending on fire season type and
geographical location of the fire. On average, our results are quite close to estimates given
by the GFED3 – the latter are +11.5% by area, and +13.2% by emissions. The
majority of carbon emissions were provided by forest fires (76.0% of the total),
followed by emissions from wetland fires (15.8%). Carbon emissions in forests
due to post fire dieback are close to the average amount of emissions caused by
burning.
Current models suggest a doubling of the number of fires by the end of this
century in the boreal zone. They predict increases of numbers of catastrophic fires
and fires covering large areas; a significant increase in the intensity of fires; and
increasing the amount and change in the composition of the gas emissions due
to enhanced soil burning. The spatial correlation between catastrophic fires and
large-scale climatic anomalies becomes more and more clear. Permafrost melting
and subsequent landscape aridity most probably will lead to the degradation and
destruction of coniferous forests, as well as to widespread distribution of “green
desertification”. Russia needs an urgent development and introduction of anticipatory strategy
of forest fire protection which would satisfy the challenges of a changing world. |
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