• Location: Andalucia, Spain; 36.98°N, 3.30°W
• Operational Management: Fluvial Dynamics and Hydrology Research Group, University of Cordoba
• Purpose/Scientific Focus: The Guadalfeo Monitoring Network (GMN) is located on the Sierra Nevada Mountain Range (Southern, Spain), a linear 80 km range, with about 40 km width, parallel to the shoreline of the Mediterranean Sea. Headwater catchments within the range are representative of Mediterranean mountain basins. That is, small to medium size mountain-coastal basins with high elevation gradients, where Alpine climate can be found in higher latitudes and Mediterranean climate in the lower ones.  The monitoring network was settled with a twofold aim: to fill the gap in the distribution of meteorological information above 1000 m a.s.l. in the area and, consequently, to be able to better understand snow dynamics over these types of environments. The weather stations that compose the network have been sequentially installed since 2004. Currently, 7 sites composed the network. The first 4 are located in the headwaters of the Guadalfeo River Basin, in the southern face of the range and the last 3 belong to the headwaters of the Genil River Basin in the north face of the range.   

• Location (Physiographic Region): The GMN is situated in the Sierra Nevada Mountain Range within the Mediterranean Biogeographical Region of Europe. In the range snow presence is seasonal above 2000 m.a.s.l. from November to May.
• Area: Guadalfeo River Basin: 1058 km²; Genil River Basin: 938 km² 
• Elevation: Guadalfeo River Basin: Mean: 1418 m; Max: 3479 m; Min: 300 m | Genil River Basin: Mean: 1270 m;  Max: 3479 m;  Min: 655 m  
• Description (Physical–Ecological–Climatic Characteristics): The GMN covers a mountain landscape compose by a complex geology mades up of thick layers of graphite schists and mica schists forming the the Nevado-Filábride complex, which constitutes the main geological unit of the Baetic. It is also a hotspot of biodiversity in the Western Mediterranean, being declared UNESCO Biosphere Reserve in 1986, Natural Park in 1989 and National Park in 1999. Alpine climate can be found in higher latitudes and Mediterranean climate in the lower ones, with presence of seasonal snow in elevations above 2000 m.   
• Drainage/River System: GMN covers two headwater catchments: the Guadalfeo River Basin, in the southern face, which drains to the Mediterranean Sea; and the Genil River Basin, which flow into the Guadalquivir River, being its main tributary.
• Site History/Historical Context: The Guadalfeo Monitoring Network (GMN) is the extension of the initial weather station at Refugio Poqueira in 2004 within the framework of the Guadalfeo Project (Andalusian Regional Government), coordinated by Miguel A. Losada from the Andalusian Institute for Earth System Research at the University of Granada, whose continuous support and inspiration made the creation of the Fluvial Dynamics and Hydrology research group in 2009 possible, which has been responsible for the GMN ever since.    
• Main Land Cover(s): Pasture, low creeping vegetation and shrubs are the main land covers at high elevation. Trees are not common, just isolated plots of reforested pine trees and some spots of oak trees are found at medium elevation. Traditional agriculture plots are present in the lower parts of the area.
• Lithology/Soils: The lithological succession in the western part of Sierra Nevada is formed by the Alpujarride complex, which is composed, in turn, by phyllites in the lower parts and to a lesser extent by quartzites that can reach a thickness of several hundreds of meters. Above them, a thick carbonate series of marbles. The upper units are composed by schists. Soils are shallow, especially in the upper part of the range.
• Mean Annual Temperature: 6.7°C
• Mean Total Annual Precipitation: 752 
• Snow Characteristics: Snow has a marked seasonal character being present above 2000 m a.s.l. from November to May. The mild winter temperatures in combination with the high long dry sunny period undergo in: (i) a highly variable snowpack, in time and space, with the presence of several accumulation and melting cycles during the snow season; (ii) a shallow snowpacks with a characteristic patchy distribution; (iii) a high snowpack density; and (iv) a non-negligible evaposublimation losses from the snowpack to the atmosphere.  High mountain hydrology is determined by the local dynamics of snow, which covers the soil surface and partially or totally the vegetation cover, decreases infiltration rates and direct runoff from precipitation during the cold periods but enhances infiltration volumes and aquifer recharge during melting periods, delays the water delivery to the fluvial network, and increases spring and summer river flows and soil moisture, extending the flow season in ephemeral rivers. 
• Years of Data: 2004 – present 

Observational Stations and Sites

 

Type	Station Name	Latitude	Longitude	Elevation	Notes/Details
Meteorological	PG1 – Tajos de Breca	37.048	-3.215	2470	Belongs to the Guadalfeo River Basin (southern face of Sierra Nevada)
Meteorological	PG2 – Refugio Poqueira	37.028	-3.323	2510	Belongs to the Guadalfeo River Basin (southern face of Sierra Nevada)
Snow	PG2N – Refugio Poqueira Nieve	37.027	-3.325	2502	Belongs to the Guadalfeo River Basin (southern face of Sierra Nevada)
Meteorological	PG3 – Contraviesa	36.871	-3.237	1332	Belongs to the Guadalfeo River Basin (southern face of Sierra Nevada)
Meteorological	PG4 – Cebadilla	37.007	-3.356	2141	Belongs to the Guadalfeo River Basin (southern face of Sierra Nevada)
Meteorological	PG5 – Cortijuela	37.083	-3.472	1675	Belongs to the Genil River Basin (northern face of Sierra Nevada)
Meteorological	PG6 – Albergue	37.094	-3.388	2507	Belongs to the Genil River Basin (northern face of Sierra Nevada)
Meteorological	PG8 – Hoya de Pedraza	37.110	-3.436	1895	Belongs to the Genil River Basin (northern face of Sierra Nevada)

Field Observation Campaigns and Other Measurements

Measurement	Station		Instrumentation Description	Height/ Depth (m)	Spatial/Temporal Resolution and Coverage
Time-lapse Photographs		PG2	CC640	3.5 m	5 image per day every 2 hours (8:00-16:00)
		PG2N	CC5MPX	2.5 m	Aug 2021 – present / 8 image per day every 2 hours (6:00 – 20:00)
		PG6	CCFC	2 m	Aug 2021 – present / 8 image per day every 2 hours (6:00 – 20:00)
		PG8	CC5MPX	2.2 m	Jul 2020 – Jun 2022 / 8 image per day every 2 hours (6:00 – 20:00)

Periodic field campaigns for in situ snow monitoring have been carried out, with different frequency, since 2004. Among them, it is interesting to highlight the snow evaposublimation campaigns (Herrero et al., 2016).

Geospatial Data

 

Available Geospatial Data	Notes (e.g., Source, Resolution, Error/Uncertainty, Date, etc.)
Elevation	Digital elevation model (DEM) with 5 m resolution— raster available from the Spanish Geographical Institute (IGN) for the whole country https://www.idee.es/csw-inspire-idee/srv/spa/catalog.search?#/metadata/spaignMDT05
Landcover and Soils	Landcover types — raster available from the Regional Environmental Information Network (REDIAM) for the whole region http://www.ideandalucia.es/catalogo/inspire/static/api/records/ 8a47da900d8fac2269ddb9e78a06c0dd7d114c63
Stream/River Network	Location of the streams, and other water bodies — shapefile available from the Regional Environmental Information Network (REDIAM) for the whole region http://www.ideandalucia.es/catalogo/inspire/srv/api/records /240fb7357b5fddf1406b802e00c87b49b5a4b365
Basin Delineation/Shapefile	Location of the catchments boundaries — shapefile available from the Regional Environmental Information Network (REDIAM) for the whole region http://www.ideandalucia.es/catalogo/inspire/srv/api/records /240fb7357b5fddf1406b802e00c87b49b5a4b365

Observational Data Availability 

• Polo, M. J., Herrero, J., Pimentel, R., and Pérez-Palazón, M. J.: The Guadalfeo Monitoring Network (Sierra Nevada, Spain): 14 years of measurements to understand the complexity of snow dynamics in semiarid regions, Earth Syst. Sci. Data, 11, 393–407, https://doi.org/10.5194/essd-11-393-2019, 2019. 

The physically based distributed hydrological model WiMMed (Watershed Integrated Model for Mediterranean Environments) was developed for better representing the hydrological cycles over these environments. Regarding snow modeling WiMMed has a snow model (SnowMed) which uses a punctual 1-layer mass and energy balance approach extended to a distributed scale using depletion curves. Actual Evapotranspiration is calculated using the Penman-Monteith PE formulation, whereas infiltration is estimated using the Green and Ampt approach in a two-layer soil discretization. Different routings for hillside and river cells are implemented. The model constitutes the basis of the Global Monitoring Systems of Snow in Sierra Nevada (GMS-SnowMed; https://www.uco.es/dfh/snowmed/). GMS-SnowMed is a web service that provides the status of snow in Sierra Nevada in quasi-real time.

Additional Information

• Aguilar C, Pimentel R, Polo MJ (2021) Two decades of distributed global radiation time series across a mountainous semiarid area (Sierra Nevada, Spain). Earth Syst Sci Data 13:1335–1359. https://doi.org/10.5194/essd-13-1335-2021 
• Herrero J, Polo MJ (2012) Parameterization of atmospheric longwave emissivity in a mountainous site for all sky conditions. Hydrol Earth Syst Sci 16:3139–3147. https://doi.org/10.5194/hess-16-3139-2012 
• Herrero J, Polo MJ (2016) Evaposublimation from the snow in the Mediterranean mountains of Sierra Nevada (Spain). Cryosph 10:2981–2998. https://doi.org/10.5194/tc-10-2981-2016 
• Herrero J, Polo MJ, Moñino A, Losada MA (2009) An energy balance snowmelt model in a Mediterranean site. J Hydrol 371:98–107. https://doi.org/10.1016/j.jhydrol.2009.03.021 
• Pérez-Palazón MJ, Pimentel R, Polo MJ et al (2018) Climate trends impact on the snowfall regime in Mediterranean mountain areas: future scenario assessment in Sierra Nevada (Spain). Water 10:720. https://doi.org/10.3390/w10060720 
• Pimentel R, Herrero J, Polo MJ (2017a) Subgrid parameterization of snow distribution at a Mediterranean site using terrestrial photography. Hydrol Earth Syst Sci 21:805–820. https://doi.org/10.5194/hess-21-805-2017 
• Pimentel R, Herrero J, Polo MJ (2017b) Quantifying snow cover distribution in semiarid regions combining satellite and terrestrial imagery. Remote Sens 9:995. https://doi.org/10.3390/rs9100995 
• Polo M, Herrero J, Aguilar C et al (2009) WiMMed, a distributed physically-based watershed model (I). Environ Hydraul Theor Exp Comput Solut 225–228, link to pdf 
• Polo MJ, Herrero J, Pimentel R, Pérez-Palazón MJ (2019) The Guadalfeo Monitoring Network (Sierra Nevada, Spain): 14 years of measurements to understand the complexity of snow dynamics in semiarid regions. Earth Syst Sci Data. https://doi.org/10.5194/essd-11-393-2019 

Contacts  

Name	Role	Contact Information
Dr. Rafael Pimentel	Assistant Professor. University of Cordoba	Email: rpimentel@uco.es Phone: +34 957 212662
Dr. Ana Andreu	Postdoctoral Researcher. University of Cordoba	Email: ana.andreu@uco.es Phone: +34 957 212662
Dr. María José Polo	Professor and head of Fluvial Dynamics and Hydrology Research Group.  University of Cordoba	Email: ana.andreu@uco.es Phone: +34 957 212662