Maps of fire occurrence – spatially explicit reconstruction of recent fire history using satellite remote sensing

Figures & data

Table 2. USGS Landsat images used to reconstruct recent fire history of selected years (number and dates of images used) and the duration in days between the first and last image used for modelling the errors.

	USGS Landsat images
Year	No	Dates	Duration*
1986	5	22/5, 31/5, 10/8, 19/8, 26/8	96
1987	9	7/4, 3/6, 10/6, 26/6, 12/7, 21/7, 7/9, 14/9, 23/9	169
1988	2	28/1, 6/12	313
1989	3	7/1, 23/6, 9/7	183
1990	1	14/8	0
1991	4	29/6, 24/7, 17/9, 3/10	96
2000	7	2/3, 20/5, 21/6, 30/6, 24/8, 2/9, 12/11	255
2001	5	9/2, 26/7, 27/7, 21/9, 14/10	247
* Difference between first and last image (in days)

Table 3. Number of fires and area burned as estimated from USGS Landsat images and as recorded from the Hellenic Forest Service together with their differences (error).

	USGS Landsat data		Forest Department		Difference
Year	Number of Fires	Total area burned	Number of Fires	Total area burned	Number of Fires	Total area burned
1986	28	2138.66	58	1395.00	−30	743.66
1987	31	1669.09	60	833.20	−29	835.89
1988	34	1169.10	70	2824.70	−36	−1655.60
1989	2	14.85	41	1909.20	−39	−1894.35
1990	11	1670.94	17	2429.20	−6	−758.26
1991	29	2937.09	14	573.90	15	2363.19
2000	18	1271.69	10	1305.70	8	−34.01
2001	15	1990.65	18	3623.00	−3	−1632.35

Table 1. Accuracy report of the classification results for the Mt. Parnitha study site.

		Reference			User accuracy	Commission error
		Burned	Non burned	Total
Classification	Burned	363	29	392	92.60%	7.40%
	Non burned	15	567	582	97.42%	2.58%
	Total	378	596	974
	Producer accuracy	96.03%	95.13%
	Omission error	3.97%	4.87%
	Overall accuracy	95.48%
	Overall error	4.52%

Table 4. Regression models of the differences in area burned against the first and last date of the Landsat images used within each year (Julian date), the number of images and the duration (last – first Julian date).

Dependent Variable	Independent Variables	Unstandardized Coefficients		Standardized Coefficients	t	Sig.
		B	Std. Error	Beta
Difference in area burned	(Constant)	−3085.02	1121.1		−2.75	.051
	NUMBER	321.81	81.8	.752	3.93	.017
	FIRST	9.8	2.6	.705	3.73	.020
	LAST	.54	3.8	.026	.14	.895
R: .929 R ^2: .863 Adjusted R ^2: .759.

Table 5. Regression models of the differences in number of fires against the first and last date of the Landsat images used within each year (Julian date), the number of images and the duration (last – first Julian date).

Dependent Variable	Independent Variables	Unstandardized Coefficients		Standardized Coefficients	t	Sig.
		B	Std. Error	Beta
Difference in number of fires	(Constant)	−86.62	42.037		−2.06	.108
	NUMBER	.89	3.068	.105	.29	.786
	FIRST	.14	.098	.516	1.43	.225
	LAST	.2	.142	.493	1.38	.240
R: .708 R ^2: .502 Adjusted R ^2: .128

Figure 1. Scatter plots between differences in area burned (estimated from USGS Landsat images – recorded from the Hellenic Forest Service) and independent variables used to model the errors (number of images, date of first and last image, duration in days between first and last image).

Figure 2. Scatter plots between differences in number of fires (estimated from USGS Landsat images – recorded from the Hellenic Forest Service) and independent variables used to model the errors (number of images, date of first and last image, duration in days between first and last image).