Geography – Physical characteristics

Climate

THE CLIMATE

Average temperature of the warmest month: 15.0 to 19.3 ºC

Average temperature of the coldest month: 3.7 to 8.7 ºC

Average annual rainfall: 919 – 1761 mm, recorded at altitudes of: 80-580 meters.

CLIMATE DATA

Inside the area a total of 9 weather stations are located, while the network of stations has been completed with those located within 5 km of the limit, considering a total of 16 stations distributed at different altitudes, from 80 to 650 m (see chart below).

Table I. Weather Stations
No.Weather stationAltitude (m)Record periodTypeData collection
1Aranga5001975-96T.P.Manual
2As Ptes. de G Rodríguez3431961-98T.P.Manual
3Fragavella*5801975-98T.P.Manual
4Guitiriz*4101971-91T.P.Manual
5Loberías 6101983-89T.P.Manual
6Lugo*4501966-98T.P.Manual
7Mondoñedo1391961-96T.P.Manual
8Monte da Curra6501986-98T.P.Manual
9Nodar*5001992-97T.P.Manual
10Outeiro de Rei*4161983-87T.P.Manual
11Punto Centro*4261969-85T.P.Manual
12Rabade*4031975-95P.Manual
13Rozas*4441985-98T.P.Manual
14Sarria5501961-98T.P.Manual
15Seara801975-95T.P.Manual
16Vilalba*4701976-98P.Manual

(*) Stations included in the area, T.P. thermopluviometric stations, P. rainfall stations.

Source: Laboratory of Botany from Martínez Cortizas & Pérez Alberti, 1999.

Thermometric records highlight the oceanic character of the mountain areas closest to the Cantabrian (Fragavella, 580 m; Loberías, 610 m) with an average temperature in the warmest month of about 15 ° C compared to interior mountain ranges (Hill of Curra, 650 m) where this parameter exceeds 18 °C, indicating a more contrasted thermal regime, with hotter and less soft summers when moving away from the damping effect of oceanic fronts. In the winter months, the thermal regime does not reflect these differences between coastal and inland mountain ranges, with measurements of the minimum temperatures of the coldest month between 5 and 6 ºC. The thermal continental nature is accentuated in the innermost valley bottoms (Sarria, 550 m), where the effects of cold air sack and the lack of thermal protection by oceanic cloud masses lower temperatures significantly.

The highest rainfall records occur in the coastal mountain ranges (Fragavella, 580 m), with annual values over 1700 mm, although this figure is increased to values over 2000 mm in the topmost sectors of the Range of Xistral (IZCO et al., 2001). The lowest values are recorded in the most inland territories of Terra Chá, as well as occasionally in valleys at very low altitude in the Cantabrian slope (Mondoñedo, 139 m, Seara, 80 m) and outside area studied.

Tabla II. Climate data of the weather stations located inland (1) and in the vicinity of the proposed area.
No.Weather stationAverage temperature of the warmest month (ºC)Average temperature of the coldest month (ºC)Rainfall (mm)
1Aranga18.26.11664
2As Ptes. de G Rodríguez17.57.01612
3Fragavella*15.05.01761
4Guitiriz*18.15.21447
5Loberías15.76.81549
6Lugo*19.36.1977
7Mondoñedo17.98.7963
8Monte da Curra18.45.71475
9Nodar*16.34.21507
10Outeiro de Rei*17.95.51029
11Punto Centro*17.45.71133
12Rabade*----1031
13Rozas*18.46.11016
14Sarria17.73.71363
15Seara18.58.4919
16Vilalba*----1179

The climatic conditions of the territory generally correspond with a temperate oceanic type, characterized by high water availability throughout the year (although lower in the summer months) and a damped thermal regime, with little seasonal temperature variation. This temperate oceanic character is reflected in the correspondence of the climate of the area with different climate classifications. Thus, according to the classification of climatic regions of the FAO-UNESCO, it is located within the humid temperate climate field, according to the climate classification Köpen-Geiger (Geiger & POHL, 1953), the general climate of the area is defined as mild and rainy, with dry and warm summers, and according to the climate classification system by Strahler (STRAHLER, 1978), it corresponds to west coast marine type summer, within the group of mid-latitude climates.

The oceanic macroclimatic character is qualified in a mesoclimatic level by the effect of the relief, distance to the sea and altitudinal gradient present in the area. Thus, there is a strong contrast in rainfall patterns, recording a difference of 1000 mm of annual precipitation between topmost sectors of the Ranges of Northern Galicia, western end of the Cantabrian and Galician Ridge facing Terra Chá, as a result of the discharge of rainfall from oceanic fronts in the mountain barriers and the lowest rate of precipitation in the lower-lying areas located leeward. As for the system of annual temperature, the existing attitudinal gradient (more than 1000 m between the extreme levels), results in the existence of a strong contrast in the measurements of annual temperature, with differences of more than 7 °C between values of the areas at lower altitudes and those near the coast compared to higher altitude areas in contact with the Cantabrian Mountains.

Evapotranspiration potential values are relatively low in the entire area, while the minimum is located in the mountain areas, due in part to the presence of increased cloud cover and air humidity, as well as to the frequency of fogs which reduce isolation rates, reducing the temperature and evapotranspiration. The water balance gains positive values for the entire area as a result of low ETP and high rainfall. However, it should be noted the presence of a large area in the middle and lower reaches of the valley of the Miño and Neira, where water availability gets values of less than 200 mm.