The authors evaluated several land surface variables from the Modern-Era Retrospective Analysis for Research and Applications (MERRA) product that are important for global ecological and hydrological studies, including daily maximum (Lnax) and minimum (Lnin) surface air temperatures, atmosphere vapor pressure deficit (VPD), incident solar radiation (SWrad), and surface soil moisture. The M ERRA...

[1] Changes in tropospheric water vapor over the Arctic are examined for the period 1979 to 2010 using humidity and temperature data from nine high latitude radiosonde stations north of 70 N with nearly complete records, and from six atmospheric reanalyses, emphasizing the three most modern efforts, MERRA, CFSR and ERA-Interim. Based on comparisons with the radiosonde profiles, the reanalyses a...

Improved understanding of the water balance in the Blue Nile is of critical importance because of increasingly frequent hydroclimatic extremes under a changing climate. The intercomparison and evaluation of multiple land surface models (LSMs) associated with different meteorological forcing and precipitation datasets can offer a moderate range of water budget variable estimates. In this context...

Atmospheric reanalyses depend on a mix of observations and model forecasts. In data-sparse regions such as the Arctic, the reanalysis solution is more dependent on the model structure, assumptions, and data assimilation methods than in data-rich regions. Applications such as the forcing of ice–ocean models are sensitive to the errors in reanalyses. Seven reanalysis datasets for the Arctic regio...

The temporal consistency of the moisture fields (precipitation, evaporation and total precipitable water) from five global reanalyses is examined over Antarctica and the Southern Ocean during 1989–2009. This concern is important given that (1) global reanalyses are known to be prone to inhomogeneities and artificial trends caused by changes in the observing system, and (2) the period of study h...

This study provides a comprehensive overview of the temperature and zonal wind biases in eight reanalysis data products, with a focus on stratospheric levels. The study identifies biases in each reanalysis from the “reanalysis mean” (defined as the mean of the MERRA, ERA-Interim, and JRA-55 reanalyses). It then examines reanalysis temperature biases with respect to HIRDLS (an independent satell...

Numerical weather prediction (NWP) models have been widely used for wind resource assessment. Model runs with higher spatial resolution are generally more accurate, yet extremely computational expensive. An alternative approach is to use data generated by a low resolution NWP model, in conjunction with statistical methods. In order to analyze the accuracy and computational efficiency of differe...

An analogue method is presented to detect the occurrence of heavy precipitation events without relying on modeled precipitation. The approach is based on using composites to identify distinct large-scale atmospheric conditions associated with widespread heavy precipitation events across local scales. These composites, exemplified in the south-central,midwestern, andwesternUnited States, are der...

Wind and Solar Energy resources are an increasingly large fraction of generation in global electricity systems. However, the variability of these resources necessitates new datasets and tools for understanding their economics and integration in electricity systems. To enable such analyses and more, we have developed a free web-based tool (Global Renewable Energy Atlas & Time-series, or GRETA) t...