Evaluating the Reliability of Air Temperature from ERA5 Reanalysis Data

TL;DR

This study assesses the accuracy of ERA5 satellite-based air temperature data by comparing it with land-based weather station data across temperate and tropical regions, revealing regional differences in reliability.

Contribution

It provides a comparative analysis of ERA5 data against ground measurements across different climate zones, highlighting factors affecting satellite data accuracy.

Findings

ERA5 performs better in temperate regions

Satellite data accuracy varies with climate and season

Milder temperatures yield more accurate satellite temperature estimates

Abstract

The reliability of ERA5 satellite-based air temperature data is under investigation in this paper. To evaluate this, the ERA5 data will be compared with land-based data obtained from weather stations on the Global Historical Climatology Network. Two climate regions are taken into consideration, temperate and tropical. Five years' worth of data is collected and compared through box plots, regression models and statistical metrics. The results show that the satellite temperature performs better in the temperate region than the tropical region. This suggests that the time of year and climate region have an impact on the accuracy of the satellite data as milder temperatures produce better approximations.