NWPStaging

In a new research article from GEO Mountains, Thornton et al. analyse the coverage of in situ climatological observations across the world's mountains. In situ, climatological data from the world's mountains are crucial for many applications. As such, any limitations associated with such data (e.g., the limited spatial density of stations, short record lengths, relative lack of observations at higher elevations, etc.) can impinge upon several important activities, not least tracking changing mountain climates, better understanding the key processes and feedbacks involved, and making reliable projections of change impacts. Despite this, patterns of in situ climatological data coverage with respect to space, time, and elevation have not yet been assessed in detail on a global basis. To begin to address this gap, in a new GEO Mountains-led research article published in Frontiers in Climate, Thornton et al. used perhaps the most comprehensive global inventory available – Global Historical Climatological Network daily (GHCNd) – to investigate and compare patterns of air temperature, precipitation, and snow depth observation record coverage across 292 named mountain regions. For the first time, additional datasets were also introduced in order to assess data coverage in more relative terms, for example with respect to the hydrological importance and size of the downstream economy of each mountain range. An 'Open Science' approach, based on exclusively open data and software, was employed throughout. The article involved collaboration with the leads of the MRI's Elevation-Dependent Climate Change and Mountain Observatories Working Groups, and was a contribution to the Frontiers Research Topic 'Knowledge Gaps from the IPCC Special Report on the Ocean and Cryosphere in a Changing Climate and Recent Advances (Volume II).' The article’s main findings are that: - Spatial patterns of mountain data coverage are highly uneven; - Station densities in several 'Water Tower Units' that were previously identified as having great hydrological importance to society are especially low; - A number of mountainous regions whose elevational distribution is severely under-sampled by GHCNd stations could be identified, and; - Mountain station density is only weakly related to the human population or economic output of the corresponding downstream catchments. Alongside the article, the authors provide a script that enables the temporal coverage (i.e., the proportion and periods of missing data vs. actual observations) and quality information (i.e., the frequency distribution of the quality flags assigned) to be efficiently presented for individual records. Since the script runs on any GHCNd station, it could provide useful applications beyond mountains. Besides being of interest to academic research groups, the article's insights should also help regional, national, and international organisations to make more informed decisions around investing in and maintaining in situ climatological monitoring efforts, such that networks are as optimised as possible (e.g., provide the most representative and informative observations at the lowest cost).