Dominant impact of residential wood burning on particulate matter in Alpine valleys during winter

Abstract

Within the project AEROWOOD (Aerosols from wood burning versus other sources), particulate matter was collected at two Swiss Alpine valleys during winter. Apportionment of aerosols from transit traffic and residential wood burning was performed using radiocarbon (14C) determinations of the organic carbon (OC) and elemental carbon (EC) fractions. On daily average, 88% and 65% of the total carbonaceous matter (including all other atoms than carbon) originated from non‐fossil sources inside and outside of the village, respectively, which is mainly attributed to wood burning. These proportions were generally higher during the evening compared to morning hours, when traffic intensity waned and heating activities increased. 14C measurements of EC indicated episodes of both nearly pure traffic and wood‐burning sources, respectively, of which the latter extreme has not been observed for EC under ambient conditions before. Results show that regulatory measures for the improvement of air quality must consider residential wood burning as an important source even in industrialized countries.

Aerosol distribution over Europe: a model evaluation study with detailed aerosol microphysics

“…8). The surprisingly high contribution of modern carbon burning during winter has also been found by Szidat et al (2007) who observed an overwhelming impact of carbonaceous aerosols from residential wood burning on particulate matter in Alpine valleys during winter-time. Until now, only little attention has been paid to residential wood burning because it was assumed to contribute only marginal to the total energy consumption in industrialized Europe.…”

“…During winter, a possible explanation is that current anthropogenic emission inventories tend to underestimate domestic wood burning in Europe. Residential heating practices are changing in Europe and the use of wood burning has increased considerably in recent years not only in rural but also in urban areas (Szidat et al, 2007) thereby reducing domestic fossil fuel heating. These developments emphasize the need to update current anthropogenic emission inventories for Europe.…”

Radiocarbon Analysis of Carbonaceous Aerosols: Recent Developments

“…[28] residential wood combustion. [30] In many other cases, however, both non-fossil OC sources co-occur in comparable amounts so that distinction is desirable. An advanced source apportionment model allows the independent estimation of OC wood so that OC bio is determined by subtraction of OCwood from OC nf .…”

“…3.5 µg m -3 EC wood for the rural site Sedel near Lucerne for January/February 2006. At the Alpine valley site Roveredo in Southern Switzerland, wood burning for residential heating was the most dominant source during winter, [30,31] >50% of EC and >80% of TC originated from local wood-burning emissions in 2004. The low contribution from fossil sources was surprising, because substantial transit traffic from the San Bernardino route passed through the village.…”

“…[16,17] Zurich and Gothenburg as European urban sites show smaller fossil contributions of ~50%, [14,15,22] which are only slightly higher than for most of the investigated European rural sites. [22,30,31] During summer, EC is nearly exclusively of fossil origin with soot production from all kinds of diesel engines as the most important source. [14,15,22] …”