Long-term Dynamics of Land Surface Temperature over Europe: Towards a Daytime normalized AVHRR Land Surface Temperature Product

Kurzfassung

In this study a statistical orbit drift correction method was applied to TIMELINE AVHRR LST from NOAA 7, 9, 11, 14, 16, 18 and 19 afternoon overpasses at 12 sites across Europe. The corrected LST anomalies were validated against Ta anomalies from nearby meteorological stations. The results showed an improvement of the correlation (R) between the LST and Ta anomalies at most sites. A few sites showed a decrease of R, which can be explained by complex land cover (urban) or missing daytime effects of LST (at forest sites). After the orbit drift correction, the long-term trends of the LST anomalies were much closer to the Ta trends. Furthermore, climatological features visible in the Ta time series (like e.g. a warm period in the late 1980s) are more distinct in the LST time series after the correction. However, similar studies reached higher correlations between LST and Ta anomalies. This can be explained by a more uniform generation of the LST and Ta anomalies. Further improvements and validation are necessary to obtain a reliable and continent-wide orbit drift correction for AVHRR. It is also planned to extend the analysis to further orbit drift correction methods and also to other validation data, e.g. Landsat LST.