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RESUMENSe ha realizado un control de calidad de datos diarios de precipitación, temperatura máxima, temperatura mínima, humedad relativa, velocidad del viento, presión atmosférica e insolación del banco nacional de datos de AEMET, para el periodo 1950-2015. Los controles realizados pertenecen a tres grupos: i) control de errores de codificación; ii) control de valores propios; y iii) comparación con vecinos. Entre los errores de codificación destacan las series de días consecutivos con un mismo valor, la repetición de cadenas de valores entre estaciones distintas, y la aparición de cadenas idénticas dentro de una misma serie. El control de valores propios consiste en detectar los valores que están fuera del umbral de la variable o que suponen un extremo sospechoso. En el control de vecinos se realiza una comparación de los datos con los registrados en estaciones vecinas para marcar posibles anomalías. Mientras que algunos controles implicarían la eliminación directa del dato, otros únicamente marcan el dato como sospechoso y requieren de un control posterior para determinar si el dato tiene que ser eliminado. Al finalizar el proceso un dato puede estar en 4 estados: dato inexistente, dato original, dato sospechoso, dato eliminado. En la aplicación de estos controles se han detectado un número elevado de errores de codificación, con afectaciones ligeramente por encima del 0.5% de la serie en temperatura y viento, mientras que los porcentajes son menores en el resto. Para la comparación con vecinos se ha testado un control con percentiles móviles a 365 días, obteniendo resultados poco satisfactorios Palabras clave: control de calidad, precipitación, temperatura, humedad relativa, velocidad del viento, presión atmosférica, insolación ABSTRACTA quality control of maximum temperature, minimum temperature, relative humidity, wind speed, atmospheric pressure and sunshine duration data from the national database of AEMET, for the period 1950-2015 has been done. Controls can be grouped into three groups: i) codification controls; ii) local values controls; and iii) neighbor comparison. Among codification controls we can find the detection of con-

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Several lines of evidence suggest that forest growth in many regions is declining as a consequence of changing climate. To predict the fate of forests in the future, a quantitative understanding of how the key climate variables (insolation, precipitation and temperature) interact with forests to cause the decline is a pressing need. Here we use a regionally-averaged tree-ring width index (RWI r) to quantify forest growth in the Southwest United States (SWUS). We show that over a period of 100 years, SWUS RWI r bifurcated into forest stands with enhanced (healthy) and reduced (declining) branches when regressed on shortwave-radiation and temperature, respectively. The reduced branch was controlled overwhelmingly by drought as measured with a regionally-averaged precipitationevapotranspiration index (SPEI r). As SPEI r approached-1.6 (previously shown as a tipping-point for SWUS conifer forest growth), RWI r approached zero and in extreme drought years, wide spread tree mortality has been observed. Modeled trends in SPEI based on four IPCC-GHG scenarios predict SWUS SPEI r falling below-1.6 more or less continuously within a few decades. With drought expanding north-and eastward over larger areas, tree mortality may become a semi-continental phenomenon with coniferous forests transitioning to more xeric ecosystems. Our results provide insights into how to differentiate functions of climate impacts on forest growth and how to identify tipping-point control parameters for forest regime transitions.

Temporal and spatial variation of shorebirds in Barra de Navidad lagoon, Jalisco, during three non-breeding seasons. Resident and migratory shorebirds inhabit different kinds of wetlands such as lagoons, rivers and seashores among others. In recent years, these areas have been importantly affected by urban, agriculture and touristic activities, such as the Barra de Navidad lagoon, for which little information is available to support conservation programs. The aim of this work was to describe shorebirds temporal and spatial distribution in Barra de Navidad lagoon during three non-breeding seasons (1999-2000, 2006-2007 and 2008-2009). For this, monthly censuses were performed from November-April with the purpose of registering all the shorebirds species. We were able to identify 19 shorebirds species (three residents and 16 winter visitors), of which Charadrius wilsonia, Limosa fedoa and Tringa semipalmata were the most abundant. The greater number of species was registered for November, December and March of the first and third seasons. The greater number of individuals was registered when birds were feeding during low tides, mainly in December, January and February of the first and third seasons. At low tide, there was a great number of species and individuals in zone C. This area had muddy substrates that were exposed during low tides and were used to feed. Barra de Navidad lagoon provided suitable habitats for feeding and resting for resident and migratory birds. Twelve of the 19 species were considered as priority within the Mexican bird conservation strategy. However, these habitats are threatened by human activities performed in the nearby areas of the lagoon that may have negative consequences for the distribution, abundance and conservation of these species.