Two new stories are now available in ESA’s HEDAVI (HEritage DAta VIsualisation) tool. HEDAVI visualises Earth observation data from satellites in ESA’s Heritage and Third Party Missions programme, and includes some data from the Copernicus Sentinel satellites.

The new stories provide a series of images acquired by the ERS, Envisat and Sentinel-1 missions, visualised over the globe, which illustrate changes to a lake in Bolivia, and celebrate ESA’s ERS-2 satellite, which returned to Earth earlier this year.

Lake Poopó drying up

Lake Poopó, which used to be the second largest lake in Bolivia, historically experienced seasonal changes, drying out in warmer months and then replenishing from the Desaguadero River during periods of rain. In recent decades, the lake experienced dramatic changes due to the El Niño phenomenon, climate change, and water diversion for local mining and agriculture.

In 2015, conditions had changed so much that the lake almost completely dried out, leaving a salt desert in its place. This has greatly affected biodiversity in the area and the local population. There have been signs of partial replenishment since 2015, but full recovery of the lake is uncertain.

The story in HEDAVI shows how the lake has changed since 1994, through a series of optical and radar images from ERS, Envisat, and Sentinel-1.

View this story in HEDAVI

 ERS-2 re-entry

The ERS-2 (European Remote Sensing) satellite re-entered Earth’s atmosphere on 21 February 2024, almost 30 years after the satellite launched.

ERS-2 was the second of two satellites in ESA’s pioneering ERS series, and acquired data of Earth’s land surface, oceans, atmosphere, and cryosphere from 1995 to 2011. Following the end of mission operations in 2011, ESA lowered the orbit of the satellite to begin a process of natural re-entry. The satellite’s orbit steadily declined since then until it safely broke apart almost 13 years later.

Data from ERS-2 are still used today, contributing to long-term studies in combination with observations from missions that followed, such as Envisat and Sentinel-1.

The story in HEDAVI celebrates this successful mission, showcasing a selection of images from ERS-2, including the first and last acquired by the satellite’s SAR instrument. The story illustrates notable milestones of the mission, and is complemented by images acquired by successor sensors, Envisat’s ASAR (Advanced Synthetic Aperture Radar) and Sentinel-1’s C-SAR.

View this story in HEDAVI