caa a22 4500 445799889 CHVBK 20180317145137.0 cr unu---uuuuu 170323e20110601xx s 000 0 eng 10.1007/s00704-010-0357-9 doi (NATIONALLICENCE)springer-10.1007/s00704-010-0357-9 Climatology of Alaskan wildfires with special emphasis on the extreme year of 2004 [Elektronische Daten] [G. Wendler, J. Conner, B. Moore, M. Shulski, M. Stuefer] Wildfires are a common experience in Alaska where, on average, 3,775km2 burn annually. More than 90% of the area consumed occurs in Interior Alaska, where the summers are relatively warm and dry, and the vegetation consists predominantly of spruce, birch, and cottonwood. Summers with above normal temperatures generate an increased amount of convection, resulting in more thunderstorm development and an amplified number of lightning strikes. The resulting dry conditions facilitate the spread of wildfires started by the lightning. Working with a 55-year dataset of wildfires for Alaska, an increase in the annual area burned was observed. Due to climate change, the last three decades have shown to be warmer than the previous decades. Hence, in the first 28years of the data, two fires were observed with an area burned greater than 10,000km2, while there were four in the last 27years. Correlations between the Palmer Drought Severity Index and the Canadian Drought Code, against both the number of wildfires and the area burned, gave relatively low but in some cases significant correlation values. Special emphasis is given to the fire season of 2004, in which a record of 27,200km2 burned. These widespread fires were due in large part to the unusual weather situation. Owing to the anticyclonic conditions of the summer of 2004, the composite anomaly of the 500mb geopotential height showed above normal values. The dominance of a ridge pattern during summer resulted in generally clear skies, high temperatures, and below normal precipitation. Surface observations confirmed this; the summer of 2004 was the warmest and third driest for Interior Alaska in a century of climate observations. The fires lasted throughout the summer and only the snowfalls in September terminated them (at least one regenerated in spring 2005). Smoke from the forest fires affected the air quality. This could be demonstrated by measurements of visibility, fine particle matter, transmissivity of the atmosphere, and CO concentration. Springer-Verlag, 2010 Wendler G. Alaska Climate Research Center, Geophysical Institute, University of Alaska Fairbanks, Fairbanks, AK, USA aut Conner J. Fairbanks North Star Borough, Fairbanks, AK, USA aut Moore B. Alaska Climate Research Center, Geophysical Institute, University of Alaska Fairbanks, Fairbanks, AK, USA aut Shulski M. Alaska Climate Research Center, Geophysical Institute, University of Alaska Fairbanks, Fairbanks, AK, USA aut Stuefer M. Alaska Climate Research Center, Geophysical Institute, University of Alaska Fairbanks, Fairbanks, AK, USA aut Theoretical and Applied Climatology Springer Vienna 104/3-4(2011-06-01), 459-472 0177-798X 104:3-4<459 2011 104 704 https://doi.org/10.1007/s00704-010-0357-9 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00704-010-0357-9 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Wendler G. Alaska Climate Research Center, Geophysical Institute, University of Alaska Fairbanks, Fairbanks, AK, USA aut NATIONALLICENCE 700 1- Conner J. Fairbanks North Star Borough, Fairbanks, AK, USA aut NATIONALLICENCE 700 1- Moore B. Alaska Climate Research Center, Geophysical Institute, University of Alaska Fairbanks, Fairbanks, AK, USA aut NATIONALLICENCE 700 1- Shulski M. Alaska Climate Research Center, Geophysical Institute, University of Alaska Fairbanks, Fairbanks, AK, USA aut NATIONALLICENCE 700 1- Stuefer M. Alaska Climate Research Center, Geophysical Institute, University of Alaska Fairbanks, Fairbanks, AK, USA aut NATIONALLICENCE 773 0- Theoretical and Applied Climatology Springer Vienna 104/3-4(2011-06-01), 459-472 0177-798X 104:3-4<459 2011 104 704 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer