Bussoleno-Chianocco, (Torino) – Piedmont (Italy) SUB -REGIONAL EURO -ALPINE NETWORK
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Bussoleno-Chianocco, (Torino) – Piedmont (Italy) SUB -REGIONAL EURO -ALPINE NETWORK DOCUMENTATION OF PAST FIRES Ignition point Fire perimeter General Topography Identification N°: 39/03 Date: August 29 th 2003 Area (ha): 483.83 Cause: anthropogenic. Type of fire: different intensities and types of fire characterized the event, depending on the different weather conditions, vegetation and on the morphology of the area. Start fire time: August 29 th 2003, h. 10.30 p.m. Final propagation time: September 7 th 2003, h.8.00 p.m. Ignition point Coordinates: UTM 353500 E; 5001420 N, south aspect, 600 m a.s.l. The fire occurred in the lower part of the Valle di Susa, valley of Susa, (Torino). Location and Comments: The fire occurred on the left-side of the Valle di Susa, Valley of Susa (Torino), on the southern slope of the mountain. It affected the territory of two municipality: Bussoleno and Chianocco. The place is characterized by high dryness worsened in the summer 2003 by the peculiar climate conditions of that season. It was a summer fire not so typical in Piedmont region as the most fire danger period is winter. The cause anthropogenic is deducible by the fact that were found on the same place, on September 8th 2001 and on January 5 th 2003, the remains of the objects used to set on the fire. It burned approximately 450 ha of forests and 30 ha of other surfaces. Forest types involved during the fire were beech forests ( Fagus sylvatica ) and other View of the mountain in October 2011. Burnt beech broad-leaf forests among which important presence trees are still evident. of Quercus pubescens (as shown on the map). The fire also involved urban-interface area. Landscape after the fire in spring 2004. During the fire, photo by CFS (State Forest Corps), Comando Stazione di Bussoleno. Landscape on the Valle di Susa, valley of Susa. The map shows the perimeter of the fire (in red), and the vegetation (Acero-tiglio-frassineti= forests of Acer spp ., Tilia cordata , Fraxinus spp ., Boscaglie pionire=pioneer forests, Castagneti= chestnut tree forests, Cespuglieti= bushes, Coltivi abbandonati= abandoned crops, Faggete= beech forests, Pinete di pino silvestre= forests of Pinus sylvestris , Praterie=grasslands, Querceti di roverella= forests of Quercus pubescens , Rocce e macereti= rocks and screes). METEOROLOGICAL SITUATION 29/8/2003 - On August 29 th , the passage of a trough connected with a low area located over Middle Northern Europe caused unfavourable weather conditions with mostly cloudy skies and local showers over Northern and Western Piedmont and strong wind. Improvement only in the late afternoon with sunny skies. 30-31/8/2003 - A weak centre of depression connected with the big low brought fair skies and sustained Foehn conditions (identified as high pressure gradient over the Piedmont Alps in “Sea level Pressure” image) caused by intense northwestern high flows over all of Piedmont. On August 31 st light increasing cloudiness and weakening winds from evening. 1÷7/09/2003 - From September 1st North-Western low level flows and afterwards an anticyclonic ridge, have supported fine weather, sunny skies, no precipitation, light wind together with sharply decreasing temperatures until September 6th . On September 7th the arrival of an Atlantic low caused a gradual worsening of weather with mostly cloudy skies and widespread precipitations in the afternoon. MONTLY ANOMALY : August 2003 was hot with very high mean temperature anomaly and dry with a very low precipitation anomaly. Danger level (FWI – Piedmont thresholds ) : 29/8/2003 LOW ; 30-31/8/2003 and 1-6/9/2003 VERY HIGH Fire danger map FIRE 29/08/2003 30 /08/2003 31 /08/2003 01 /0 9/2003 02 /0 9/2003 Danger level : 0 - VERY LOW 1 - LOW 2 - MODERATE 3 - HIGH 4 - VERY HIGH 1. Air temperature and relative humidity 35 30 25 20 Temperature15 [°C] 10 5 0 27/8/03 0:00 100 27/8/03 12:00 90 80 70 60 RH [%] 28/8/03 0:00 "Chianocco-Bussoleno" Fire 29/08/2003 50 40 30 20 28/8/03 12:00 10 MONTLY ANOMALY 0 29/8/03 0:00 Hourly Air Temperature [°C] 27/8/03 0:00 29/8/03 12:00 27/8/03 12:00 30/8/03 0:00 "Chianocco-Bussoleno" Fire 29/08/2003 28/8/03 0:00 . 30/8/03 12:00 mean temperature anomaly August 2003 28/8/03 12:00 31/8/03 0:00 29/8/03 0:00 Hourly Relative Humidity [%] 31/8/03 12:00 29/8/03 12:00 1/9/03 0:00 30/8/03 0:00 : 1/9/03 12:00 date 30/8/03 12:00 2/9/03 0:00 31/8/03 0:00 2/9/03 12:00 31/8/03 12:00 3/9/03 0:00 1/9/03 0:00 3/9/03 12:00 date 1/9/03 12:00 4/9/03 0:00 2/9/03 0:00 4/9/03 12:00 2/9/03 12:00 Hourly data 5/9/03 0:00 Daily mean data 3/9/03 0:00 precipitation anomaly 5/9/03 12:00 3/9/03 12:00 6/9/03 0:00 4/9/03 0:00 6/9/03 12:00 4/9/03 12:00 7/9/03 0:00 5/9/03 0:00 7/9/03 12:00 Fire activity period 5/9/03 12:00 8/9/03 0:00 6/9/03 0:00 6/9/03 12:00 Temperature Humidity [%] 7/9/03 0:00 [° C] Relative 7/9/03 12:00 August 2003 8/9/03 0:00 2. Wind speed 10 9 8 7 Wind Speed6 [m/s] 5 4 3 3. 2 1 0 Fire weather indices 27/8/03 0:00 90 85 27/8/03 12:00 80 75 70 65 60 danger level "Chianocco-Bussoleno" Fire 29/08/2003 55 28/8/03 0:00 50 FWI index45 40 35 30 25 28/8/03 12:00 20 15 10 danger level 5 danger level 4 0 29/8/03 0:00 danger level danger level 29/8/03 12:00 Hourly Wind Speed [m/s] 100 24/8/03 90 3 30/8/03 0:00 80 2 "Chianocco-Bussoleno" Fire 29/08/2003 70 FWI index 1 60 0 50 25/8/03 30/8/03 12:00 40 30 20 10 31/8/03 0:00 0 26/8/03 31/8/03 12:00 31/7/03 FWI index and threshold 1/8/03 1/9/03 0:00 FWI 27/8/03 ISI 2/8/03 "Chianocco-Bussoleno" Fire 29/08/2003 1/9/03 12:00 3/8/03 28/8/03 4/8/03 date 2/9/03 0:00 87.0 5/8/03 36.0 6/8/03 7.2 2/9/03 12:00 29/8/03 7/8/03 START 8/8/03 3/9/03 0:00 9/8/03 ISI 30/8/03 3/9/03 12:00 10/8/03 11/8/03 and FWI index 4/9/03 0:00 12/8/03 31/8/03 45.6 date 4/9/03 12:00 13/8/03 33.5 14/8/03 5/9/03 0:00 15/8/03 1/9/03 16/8/03 5/9/03 12:00 36.6 17/8/03 2/9/03 18/8/03 6/9/03 0:00 date 19/8/03 threshold change 31.6 6/9/03 12:00 20/8/03 3/9/03 21/8/03 7/9/03 0:00 22/8/03 30.2 23/8/03 4/9/03 7/9/03 12:00 24/8/03 Fire activity 25/8/03 8/9/03 0:00 period 5/9/03 26/8/03 34.7 27/8/03 [km/h] 28/8/03 6/9/03 Wind speed 29/8/03 26.8 END 30/8/03 The fire danger level determined by the Fire 31/8/03 Weather Index ( 7/9/03 was LOW 1/9/03 ignited, because FWI is calculated from weather conditions at 2/9/03 12am, but the strong wind supporting the 3/9/03 fire propagation 8/9/03 affected the region in 60 the afternoon. In the 4/9/03 next days the FWI 50 index increased at 5/9/03 40 VERY HIGH 30 when the fire 6/9/03 20 7/9/03 10 The FWI follows the trend of 0 ISI index 8/9/03 Spread Index), a good predictor of the fire. Please notice the sharp increased of ISI on August 31 FWI) Foehn wind. Fire activity . ISI st period (Initial for strong FWI ISI "Chianocco-Bussoleno" Fire 29/08/2003 The FFMC (Fine Fuel FFMC index Moisture Code) was 100 high with values near 100 during the days of 90 90.4 fire, and these values 80 80.3 show a very low rate of 70 the moisture content of 60 surface litter and other cured fine fuels, hence 50 a heavy dehydration of FFMC index 40 the layer. 30 20 FFMC 10 0 1/8/03 2/8/03 3/8/03 4/8/03 5/8/03 6/8/03 7/8/03 8/8/03 9/8/03 1/9/03 2/9/03 3/9/03 4/9/03 5/9/03 6/9/03 7/9/03 8/9/03 31/7/03 10/8/03 11/8/03 12/8/03 13/8/03 14/8/03 15/8/03 16/8/03 17/8/03 18/8/03 19/8/03 20/8/03 21/8/03 22/8/03 23/8/03 24/8/03 25/8/03 26/8/03 27/8/03 28/8/03 29/8/03 30/8/03 31/8/03 date Fire activity period "Chianocco-Bussoleno" Fire 29/08/2003 DMC and DC index 900 200 850 180 DC 800 835.7 DMC 160 750 779.3 140 700 650 126.0 120 The high values of 600 100 DMC (Duff Moisture 97.7 DC index Code) and DC 550 80 DMC index 500 (Drought Code) show a 60 low moisture content in 450 40 deep soil layer and in 400 DC the mean soil layer.