Published on 10 June 2020
In the last decade, climate change has taken centre stage in both the public and scientific arenas, as increasingly extreme weather and human impact on the environment have become more apparent. Debates and calls to action have fuelled interest in long-term science and environmental monitoring applications, with satellite data and remote sensing emerging as key contributors to this new wave of climatological research.
Documenting human-made changes from space and monitoring global conditions that are particularly relevant for climatological studies, remote sensing combines ground measurements and climate model results with Essential Climate Variables (ECVs) as defined by the Global Climate Observing System (GCOS) and tracked through satellite data.
However, the World Meteorological Organisation (WMO) reported that at least 30 years of data are necessary to detect statistically significant changes of ECVs.
As early as 2008, ESA recognised the importance of long time-series of datasets in determining changes in the planet's climate and launched the Long Term Data Preservation (LTDP) programme, to preserve these valuable data for future generations. The programme’s aim was to ensure that older data would continue to be accessible and usable after many years. The LTDP was extended in 2016 under a new name: the Heritage Space Programme.
These two figures show the anomaly of Lake Surface Water Temperature between 1981 – 2016 for Lake Bolsena near Rome, in Italy, and Lake Inarijärvi in northern Finland. A difference can be clearly seen, with the northern regions experiencing increased warming, in comparison to the Mediterranean area. The image gives the final trend analysis showing a warming trend at all locations, rising from 0.2 K/decade in the 1980s to 0.8 K/decade in the 2010s. A gradient of increasing trends from south-west to north-east of Europe was discovered. The data used was from the nearly 40 years of Advanced Very High Resolution Radiometer (AVHRR) data consolidated and harmonised under the frame of ESA's Heritage Space Programme.