New ESA mission. Could it be that urban heat islands will be more visible from space?

27.9.2022 10:01 PM
New ESA mission. Could it be that urban heat islands will be more visible from space?

Recent heatwaves are particularly troublesome for residents of large cities. Scientists, trying to combat this negative phenomenon, collect detailed information about temperature distribution. The new mission of the European Space Agency is designed to provide accurate data on surface temperatures occurring in a given area.

What are urban heat islands?

Urban heat islands (MWCs) are a meteorological phenomenon that occurs in metropolitan areas characterized by dense and high-rise buildings. Urban spaces have higher temperature indices compared to undeveloped areas due to too much concrete and too little flora. In the case of this concept, the word "island" refers to the image of concentric isotherms whose values ​​decrease as you move away from the city center. Plotted on the city map, their shape resembles "islands" surrounded by the sea, ie a cooler area marked in blue on the plan. The warmest areas are industrial and downtown.

MWCs are defined by parameters such as intensity, structure, and horizontal and vertical range. The highest intensities of the islands can be observed in summer when the temperature differences between the city and the outskirts are greatest. The horizontal range is related to the buildings. On the other hand, the size of the vertical range depends on the size of cities or industrial zones and can be up to several hundred meters. The structure of the MWC has visible heat centers that separate areas of cooler air.

How is the reading of urban heat islands as seen from space expected to be improved?

Information on the temperature of the Earth's surface is collected using remote sensing satellites. One of the most famous missions was Sentinel-3 by ESA. Its disadvantage, however, was the poor resolution of the obtained data, which was 1 km, and did not allow for accurate and precise observation of urban heat island phenomena.

Currently, for better resolution, the European Space Agency (ESA) is organizing the Land Surface Temperature Monitoring (LSTM) mission, which will collect accurate information on surface temperatures with a resolution of up to 20 times better than that obtained by the Sentinel-3 mission.

Recent heatwaves have broken records in both Europe and the US, so NASA scientist Glynn Hulley emphasizes the importance of efficient identification of hot regions, supported by data collected during the latest mission.

Interestingly, to test the effectiveness of the mission, ESA conducted a trial mission. Its purpose was to check the effectiveness of the sensor to be installed on the satellite. For this purpose, ECOSTRESS, an infrared thermal data collection instrument that collects data of a similar quality to be offered by the LSTM mission, was used. It turned out that the collected data showed the surface temperature at a resolution of 50 meters for Prague and Paris.

Benjamin Koetz from ESA emphasizes how useful the tested sensor turned out to be, which will be used during the European LSTM mission. It is to measure surface temperatures with a resolution of approximately 50 meters.

What are the advantages of the newest mission?

The information collected in higher resolution offers a much higher quality and level of data analysis compared to the Sentinel-3 mission. Due to this, city planners and surveyors will have the opportunity to better plan urban space to effectively reduce the negative impact of heat, and farmers will receive information about crops that require better irrigation.

At the moment, it is known that the LSTM satellite is to be in orbit around the Earth by the end of this decade.