Table 4. Climatic parameters measured on field site during the two study years 2008 and 2009 with reference period 1961–1990 measured by the German Weather Service DWD in Jena, city center.

Month	Air temperature (°C)			Precipitation (mm)			Soil moisture (Vol%)
	1961–90	2008	2009	1961–90	2008	2009	2008	2009
J	0.40	5.00	−3.09	37.00	24.50	9.00	37.29	22.11
F	1.40	3.76	1.15	34.00	20.40	33.70	37.15	33.31
M	4.80	5.11	5.04	43.00	55.80	42.50	37.97	37.01
A	8.60	7.90	11.58	57.00	91.80	73.70	37.35	31.39
M	13.40	14.05	13.89	62.00	22.00	62.60	25.62	31.05
J	16.70	17.13	15.01	75.00	54.40	52.90	21.74	28.58
J	18.20	18.51	18.34	52.00	40.60	85.10	17.75	31.29
A	17.40	17.90	18.59	63.00	58.60	14.60	16.61	22.34
S	14.20	12.05	14.56	42.00	50.00	53.60	21.71	23.67
O	9.80	9.13	8.42	39.00	55.30	47.30	26.30	28.70
N	5.00	5.60	8.06	41.00	19.90	68.30	28.16	34.00
D	1.70	1.28	0.64	42.00	38.60	80.00	30.59	36.22
Year	9.30	11.75	11.48	587.00	531.90	623.30	28.19	29.97

Values represent monthly means (temperature, soil moisture) or sums (precipitation).