About

Land Surface Temperature (LST) is an important variable within the Earth climate system. It describes processes such as the exchange of energy and water between the land surface and atmosphere, and influences the rate and timing of plant growth.

Accurately understanding LST at the global and regional level helps to evaluate land surface–atmosphere exchange processes in models and, when combined with other physical properties such as vegetation and soil moisture, provides a valuable metric of surface state.

LST also provides independent temperature data to complement in situ measurements and reanalysis associated with near-surface air temperature – a fundamental target outlined in the UNFCCC Paris agreement.

The LST_cci project aims to provide an accurate view of temperatures across land surfaces globally over the past 20 to 25 years and meet the requirements of Global Climate Observing System (GCOS) for climate applications by developing techniques to merge archived data from a variety of satellites into a combined long-term satellite record for climate.

Objective

• The ultimate objective of the LST_cci project is to provide the following results:
• An expected accuracy and precision of all the LST ECV Products of < 1 K
• A first assessment of the stability of LST ECV Products
• A first global LST CDR with record length over 25 years
• A first passive microwave time series with record length of over 20 years
• Intercalibration and time difference corrections of level-1 data for CDRs
• Retrieval algorithm consistency across LST ECV products and CDRs
• Consistency of uncertainty approach
• Optimisation of the best cloud clearing detection across new sensors
• Demonstration of seamless end-to-end LST ECV production for complete multi-mission archives
• Fully independent and rigorous product validation and intercomparison extended to new sites and external data sets
• Publications in world-leading journals demonstrating climate application exploitation of LST ECV Products
• Significantly increase the maturity levels of all LST ECV products

About the project

The project will more specifically provide the following results:

• A strong validation component providing globally representative and consistent in-situ validation and intercomparison of LST products over all the major land cover types, informing the climate community of the performance of the LST ECV products
• Sustained support to the surface temperature community through dedicated effort into the well-established International LST and Emissivity Working Group (ILSTE) which is the principle forum of community expertise from data providers to users
• Detailed climate user input into the specifications of the LST ECV products, and user assessment of these products to drive LST exploitation in climate science
• Strong buy-in from the climate science community coordinated by the Climate Research Group, with key inputs from the CMUG and CSWG, and user interaction at two dedicated user workshops
• A comprehensive suite of high quality IR LST ECV Products and MW LST ECV Products for geostationary (GEO) and low earth orbit (LEO) satellites covering a range of time periods from 1995 for the earliest sensor through to 2020 for many current and some future sensors
• A first merged IR CDR from input bias corrected Level-1 GEO and LEO data at 0.05° and 3-hourly. This system specification will confront the expected requirements for an operational LST climate service.
• A consistent long-term LST CDR of 25 years from 1995 to 2020 for ATSR-2 through to SLSTR by bridging and filling the gap between AATSR and SLSTR
• Demonstration of a coherent and open pre-operational End-to-End processing system for delivering the LST ECV Products to the climate user community
• A strong validation component providing globally representative and consistent in-situ validation and intercomparison of LST products over all the major land cover types, informing the climate community of the performance of the LST ECV products with respect to the GCOS requirements
• Sustained support to the surface temperature community through dedicated effort into the well-established International LST and Emissivity Working Group (ILSTE) which is the principle forum of community expertise from data providers to users