Generation of Monthly Precipitation Climatologies for Costa Rica Using Irregular Rain-Gauge Observational Networks

Abstract

Precipitation climatologies for the period 1961–1990 were generated for all climatic regions of Costa Rica using an irregular rain-gauge observational network comprised by 416 rain-gauge stations. Two sub-networks were defined: a high temporal resolution sub-network (HTR), including stations having at least 20 years of continuous records during the study period (157 in total); and a high spatial resolution sub-network (HSR), which includes all HTR-stations plus those stations with less than 20 years of continuous records (416 in total). Results from the kriging variance reduction efficiency (KRE) objective function between the two sub-networks, show that ordinary kriging (OK) is unable to fully explain the spatio-temporal variability of precipitation within most climatic regions if only stations from the HTR sub-network are used. Results also suggests that in most cases, it is beneficial to increase the density of the rain-gauge observational network at the expense of temporal fidelity, by including more stations even though their records may not represent the same time step. Thereafter, precipitation climatologies were generated using seven deterministic (IDW, TS2, TS2PARA, TS2LINEAR, TPS, MQS and NN) and two geostatistical (OK and KED) interpolation methods. Performance of the various interpolation methods was evaluated using cross validation technique, selecting the mean absolute error (MAE) and the root-mean square error (RMSE) as agreement metrics. Results suggest that IDW is marginally superior to OK and KED for most climatic regions. The remaining deterministic methods however, considerably deviate from IDW, which suggests that these methods are incapable of properly capturing the true-nature of spatial precipitation patterns over the considered climatic regions. The final generated IDW climatology was then validated against the Global Precipitation Climatology Centre (GPCC), Climate Research Unit (CRU) and WorldClim datasets, in which overall spatial and temporal coherence is considered satisfactory, giving assurance about the use this new climatology in the development of local climate impact studies.

Performance Evaluation of Bias Correction Methods for Climate Change Monthly Precipitation Projections over Costa Rica

“…Consequently, the uncorrected PRECIS outcomes are preferred over their bias corrected counterparts over the South-Pacific and Caribbean climatic regions during DJF. Contrastingly, during DJF the GPCC climatology generally benefited from bias correction for all climatic regions except for the South-Pacific regions, an issue that has been previously identified and analyzed Mendez et al [82]. In this case, EQM scores slightly higher in terms of RMSE, MAE and R but PTR yields equally satisfactory performances.…”

“…A 1x1 km gridded monthly precipitation climatology based on rain-gauge historical observations ( Figure 1) provided by Instituto Meteorológico of Costa Rica (IMN) [82,83] was selected as the observational dataset for the period 1951-1995. The Global Precipitation Climatology Centre (GPCC) [84] dataset was used on a comparative basis to evaluate the overall spatial and temporal coherence of the locally generated IMN climatology.…”

Tropical glacier reconstructions during the Last Glacial Maximum in Costa Rica

“…These are intermittent with a minimum in July and August known as the Mid-Summer Drought (Maldonado et al, 2016), however, the dry season generally occurs from December to April with average temperatures of 9.7 °C (Figure 2; Quesada-Román 2016, 2017). The temporal and spatial variability of rainfall in the country is heavily influenced by the El Niño-Southern Oscillation (ENSO; Méndez et al, 2019;Quesada-Román and Pérez-Briceño, 2019). According to Waylen and Laporte (1999), complex and contrasting responses (i.e., warm or wet) vary in terms of their signs, magnitude, duration, and seasonality between catchment areas draining to the Pacific and those flowing into the Caribbean Seas.…”

Avistamientos de <i>Orcinus orca</i> (Linnaeus, 1758) (Cetartiodactyla: Odontoceti: Delphinidae) en el Pacífico costarricense (1990-2020)

“…Aunque no existen registros en el país de orcas cazándolas, se sabe que en otros sitios las depredan con frecuencia (Steiger et al 2008). Con respecto a octubre, las condiciones, por lo general lluviosas, en nuestro país (Mendez et al 2019) podrían influenciar la falta de observaciones, pues complicarían la navegación y visibilidad, pero también deben tomarse en cuenta los fenómenos migratorios propios de las ballenas, antes descritos.…”