Human-caused wildfire risk rating for prevention planning in Spain (original) (raw)

Emissions from forest fires near Mexico City

Atmospheric Chemistry and Physics, 2007

The emissions of NO x and HCN (per unit amount of fuel burned) from fires in the pine-savannas that dominate the mountains surrounding Mexico City (MC) are about 2 times higher than normally observed for forest burning. The NH 3 emissions are about average for forest burning. The NO x /VOC mass ratio for the MC-area mountain fires was ∼0.38, which is similar to the NO x /VOC ratio in the MC urban area emissions inventory of 0.43, but much larger than the NO x /VOC ratio for tropical forest fires in Brazil (∼0.068). The nitrogen enrichment in the fire emissions may be due to deposition of nitrogen-containing pollutants in the outflow from the MC urban area. This effect may occur worldwide wherever biomass burning coexists with large urban areas (e.g. the tropics, southeastern US, Los Angeles Basin). The molar emission ratio HCN/CO for the mountain fires was ∼0.0128± 0.0096: 2-9 times higher than widely used literature values for biomass burning. The MC-area/downwind molar ratio of HCN/CO is about 0.003±0.0003. Thus, if other types of biomass burning are relatively insignificant, the mountain fires may be contributing about 23% of the CO production in the . Comparing the PM10/CO mass ratio in the MC Metropolitan Area emission inventory (0.011) to the PM1/CO mass ratio for the mountain fires (0.133) then suggests that these fires could produce as much as ∼78% of the fine particle mass generated in the MC-area.

Large wildland fires and extreme temperatures in Sardinia (Italy)

iForest - Biogeosciences and Forestry, 2014

Heat-wave events are commonly recognized as adverse impacts on agriculture, forests, and economic activities. Several studies showed that future climate changes in the western Mediterranean Basin will lead to an increase in extreme weather events, mainly in the summer season. For this reason, it is crucial to improve our knowledge on the effects of extreme temperature events on wildland fire activity. This work analyses the relation between high temperature days (air temperature higher than 25°C at 850 hPa) and large wildland fires in Sardinia (Italy) during the period 1991-2009. Our results showed that the influence of high temperature days on large wildland fires was remarkable. Neither the number of fires nor the area burned decreased under high temperature days, although a decrease of both parameters was observed on other days. Additionally, the average size of fires, the probability of large fire occurrence, the daily area burned and daily number of fires were higher on high temperature days.