The Association Between Circulation Anomaliesin the Mid-Troposphere and Area Burnedby Wildland Fire in Canada

Skinner, W.; Stocks, B. J.; Martell, David L.; Bonsal, Barrie; Shabbar, Amir

doi:10.1007/s007040050095

Cited by 168 publications

(148 citation statements)

References 24 publications

Supporting

Mentioning

137

Contrasting

Order By: Relevance

“…Johnson & Wowchuk 1993). Several authors have found empirically that the most fire-prone situations occur when the upper air ridge is located directly above or immediately upstream of the area burned (Street & Birch 1986;Skinner et al 1999;Macias Fauria & Johnson 2006). Thus, the frequency of mid-tropospheric blocking highs relates to a large area burned in the boreal forest.…”

Section: The Relationship Between Fire and Climatementioning

confidence: 99%

“…The main features of the normal climatological summer (fire season) flow in northern North America for the last half of the twentieth century (figure 4) are (i) a weak southward-extending trough located adjacent to the west coast of North America-the west coast trough (WCT), (ii) a parallel strong northwardextending ridge over western and northwestern North America, ranging from the west coast to approximately 1108 W and extending from the midlatitudes to Alaska-the western Canadian ridge (WCR), (iii) a strong southward-extending trough over northeastern North America-the Canadian Polar trough (CPT; Skinner et al 1999) and, finally (iv) upper air height variability over the Arctic Ocean (figure 5, see below).…”

Section: The Relationship Between Fire and Climatementioning

confidence: 99%

“…Large fires are usually linked to positive 500 hPa anomalies that correspond to amplifications (eastward, northward and northwestward) of an anomalously strong WCR and to an eastward shifted and sometimes weakened CPT (Skinner et al 1999;Macias Fauria & Johnson 2006 Thompson & Wallace 1998 is defined as the dominant pattern of sea-level pressure (SLP) variations north of 208 N and is characterized in its positive (negative) phase by negative (positive) SLP anomalies in the Arctic and positive (negative) anomalies at mid-latitudes (figure 5). The AO pattern is found to extend from the surface to the stratosphere, hence reflecting the strength of the polar vortex (Thompson & Wallace 1998;Serreze et al 2000).…”

Section: The Relationship Between Fire and Climatementioning

confidence: 99%

See 2 more Smart Citations

Climate and wildfires in the North American boreal forest

Fauria

Johnson

2007

Phil. Trans. R. Soc. B

126

View full text Add to dashboard Cite

The area burned in the North American boreal forest is controlled by the frequency of midtropospheric blocking highs that cause rapid fuel drying. Climate controls the area burned through changing the dynamics of large-scale teleconnection patterns (Pacific Decadal Oscillation/El Niñ o Southern Oscillation and Arctic Oscillation, PDO/ENSO and AO) that control the frequency of blocking highs over the continent at different time scales. Changes in these teleconnections may be caused by the current global warming. Thus, an increase in temperature alone need not be associated with an increase in area burned in the North American boreal forest. Since the end of the Little Ice Age, the climate has been unusually moist and variable: large fire years have occurred in unusual years, fire frequency has decreased and fire-climate relationships have occurred at interannual to decadal time scales. Prolonged and severe droughts were common in the past and were partly associated with changes in the PDO/ENSO system. Under these conditions, large fire years become common, fire frequency increases and fire-climate relationships occur at decadal to centennial time scales. A suggested return to the drier climate regimes of the past would imply major changes in the temporal dynamics of fire-climate relationships and in area burned, a reduction in the mean age of the forest, and changes in species composition of the North American boreal forest.

show abstract

Section: The Relationship Between Fire and Climatementioning

confidence: 99%

Section: The Relationship Between Fire and Climatementioning

confidence: 99%

Section: The Relationship Between Fire and Climatementioning

confidence: 99%

See 1 more Smart Citation

Climate and wildfires in the North American boreal forest

Fauria

Johnson

2007

Phil. Trans. R. Soc. B

126

View full text Add to dashboard Cite

show abstract

“…Large forest fires in boreal Canada are often associated with upper level longwave ridging at boreal latitudes (Skinner et al 1999(Skinner et al , 2002. These large and persisting blocking high-pressure systems in the upper atmosphere cause air subsidence, resulting in typically sunny, warm days that lead to dry fuel conditions that can extend to several hundreds of kilometres (Newark 1975;Johnson and Wowchuk 1993;Bessie and Johnson 1995;Skinner et al 1999Skinner et al , 2002.…”

Section: Introductionmentioning

confidence: 99%

“…These large and persisting blocking high-pressure systems in the upper atmosphere cause air subsidence, resulting in typically sunny, warm days that lead to dry fuel conditions that can extend to several hundreds of kilometres (Newark 1975;Johnson and Wowchuk 1993;Bessie and Johnson 1995;Skinner et al 1999Skinner et al , 2002. When the high-pressure systems have significant moisture or begin to break down, convective activity leading to numerous lightning strikes occurs and these ignite forest fires (Nash and Johnson 1996).…”

Section: Introductionmentioning

confidence: 99%

A 229-year dendroclimatic-inferred record of forest fire activity for the Boreal Shield of Canada

Girardin

Tardif

Gauthier

et al. 2006

Int. J. Wildland Fire

View full text Add to dashboard Cite

Abstract. Six independent tree-ring reconstructions of summer drought were calibrated against instrumental fire data to develop a 229-year dendroclimatic-inferred record of fire activity (annual area burned and fire occurrence) on the Boreal Shield, Canada. As a means of validating the statistical reconstructions of the fire activity, a comparison was made with a stand age distribution derived from a regional time-since-last-fire map for an area located at the transition between the mixedwood and coniferous boreal forests of south-western Quebec. Calibration statistics indicated that 31% of the area burned variance and 45% of the fire occurrence variance could be accounted for by the six drought reconstructions. The verification statistics indicated a tendency for the statistical reconstructions of the fire activity to reproduce with confidence both high and relatively low frequency variations in fire. Episodes of succeeding years with important fire activity were estimated for

show abstract

Quantifying the potential for high-altitude smoke injection in the North American boreal forest using the standard MODIS fire products and subpixel-based methods

Peterson

Hyer

Wang

2014

J. Geophys. Res. Atmos.

View full text Add to dashboard Cite

All chemical transport models require an estimation of the vertical distribution of smoke particles near the source. This study quantitatively examines the strengths and weaknesses of several fire products for characterizing plume buoyancy and injection heights in the North American boreal forest during [2004][2005]. Observations from the Multiangle Imaging Spectroradiometer show that 21% of smoke plumes are injected more than 500 m above the boundary layer (BL 500 ) and 8% exceed 2.5 km above ground level. Corresponding observations from the Moderate Resolution Imaging Spectroradiometer (MODIS) show that probability of injection above the BL 500 exceeds 60% for pixel-based fire radiative power (FRP p ) values abovẽ 2500 MW. Increasing values of subpixel-retrieved fire area and temperature also correspond to higher injections but only after removing fire pixels with a weak 11 μm fire signal and clustering. The probability of injection above the BL 500 reaches 50% when the subpixel radiant flux (FRP f flux) exceeds 20 kW/m 2 , highlighting its potential for estimating plume buoyancy. However, these data have limitations similar to FRP p , where the highest probability of injection corresponds to a small percentage of the data set (5-18%), and many high-altitude injections occur with lower values. Examinations of individual smoke plumes highlight the importance of combining pixel-level and subpixel outputs and show that plume injection is also sensitive to the fire pixel spatial distribution and meteorology. Therefore, an optimal method for predicting high-altitude injections will require some combination of injection climatology, FRP p , FRP f flux, and meteorology, but each variable's importance will depend on fire event characteristics.

show abstract

The Association Between Circulation Anomaliesin the Mid-Troposphere and Area Burnedby Wildland Fire in Canada

Cited by 168 publications

References 24 publications

Climate and wildfires in the North American boreal forest

Climate and wildfires in the North American boreal forest

A 229-year dendroclimatic-inferred record of forest fire activity for the Boreal Shield of Canada

Quantifying the potential for high-altitude smoke injection in the North American boreal forest using the standard MODIS fire products and subpixel-based methods

Contact Info

Product

Resources

About