ICE-IMPACT: International Consortium for the Exploitation of Infrared Measurements of PolAr ClimaTe
Lead Research Organisation:
Imperial College London
Department Name: Physics
Abstract
The Far infra red (FIR) is defined as the region of electromagnetic spectrum found at wavelengths greater than 15 microns. FIR radiation plays a major role in the Earth's energy balance, accounting for approximately half of the emission to space from the Earth and its atmosphere in the global mean. Fundamental physics implies that FIR radiation will play an even more important role in influencing climate variability and change in the fragile polar regions. The very cold surface temperatures found in these locations means that a greater fraction of the emitted surface energy is found at longer wavelengths. Moreover, the associated very low water vapour concentrations typically found in polar regimes effectively open up 'windows' in the FIR, making it possible to see further into the atmosphere from the ground than would normally be possible at these wavelengths. By the same argument, more of the surface energy emitted at these wavelengths is able to escape to space.
Recent work has suggested that assumptions about FIR surface characteristics made in many of the most advanced models that we use to predict climate - termed Earth-system models - mean that they may be missing an important polar climate feedback process. This could lead to an additional Arctic surface warming of up to 2 K by the 2030s which would be expected to affect the rate of ice-melt and sea-level rise. Termed the 'ice-emissivity' feedback, the mechanism depends on the fact that snow and ice emit more energy at FIR wavelengths than sea-water at the same temperature. Current Earth-system models typically assume that all surfaces have the same emissivity in the FIR and so do not include this feedback process. These same models also struggle to match surface observations of the downwelling radiation emitted by the atmosphere in polar regions, a shortcoming that is believed to be principally due to inadequacies in the representation of polar clouds. However, up to now a detailed evaluation of the polar radiation budget has been hampered by a lack of dedicated observations spanning the entire infrared, including the FIR.
This project seeks to address this deficiency by bringing together a team of international experts in FIR research and climate modelling to develop a suite of observationally based tools which will be used to assess model performance and drive future improvements. In the course of this work we will derive the first ever assessment of FIR surface emissivity from in-situ airborne observations over the Greenland plateau; characterise the infrared surface radiation budget over Antarctica and assess the meteorological processes driving variability there over a range of time-scales; evaluate approaches used to derive synthetic FIR measurements from space-based observations; and begin the process of quantifying the ice-emissivity feedback in two leading Earth-system models.
Recent work has suggested that assumptions about FIR surface characteristics made in many of the most advanced models that we use to predict climate - termed Earth-system models - mean that they may be missing an important polar climate feedback process. This could lead to an additional Arctic surface warming of up to 2 K by the 2030s which would be expected to affect the rate of ice-melt and sea-level rise. Termed the 'ice-emissivity' feedback, the mechanism depends on the fact that snow and ice emit more energy at FIR wavelengths than sea-water at the same temperature. Current Earth-system models typically assume that all surfaces have the same emissivity in the FIR and so do not include this feedback process. These same models also struggle to match surface observations of the downwelling radiation emitted by the atmosphere in polar regions, a shortcoming that is believed to be principally due to inadequacies in the representation of polar clouds. However, up to now a detailed evaluation of the polar radiation budget has been hampered by a lack of dedicated observations spanning the entire infrared, including the FIR.
This project seeks to address this deficiency by bringing together a team of international experts in FIR research and climate modelling to develop a suite of observationally based tools which will be used to assess model performance and drive future improvements. In the course of this work we will derive the first ever assessment of FIR surface emissivity from in-situ airborne observations over the Greenland plateau; characterise the infrared surface radiation budget over Antarctica and assess the meteorological processes driving variability there over a range of time-scales; evaluate approaches used to derive synthetic FIR measurements from space-based observations; and begin the process of quantifying the ice-emissivity feedback in two leading Earth-system models.
Planned Impact
In the short-term the most obvious socio-economic benefit is an improved predictive ability for the UK in the polar regions, incorporating a physical mechanism, the 'ice-emissivity' feedback, that is missing in the current version of UKESM. This mechanism has been shown to have the potential to significantly increase the rate of temperature change in the Arctic and hence has important implications for both the region itself and further afield. Enhanced temperatures would be expected to result in accelerated ice-melt, with consequences for the rate of sea-level rise. They may also encourage permafrost melt and associated methane release, creating a further, positive feedback loop. Through the course of this project we will engage the wider, international modelling community, first via our project partners and then through a dedicated project workshop (W2 - see case for support/Pathways to Impact), in order that this benefit is translated beyond the immediate ICE-IMPACT team. Obvious links can also be made with proposed cross-centre NERC projects focused on UKESM and the North Atlantic Climate System, both of which have NCEO involvement.
Looking longer-term, a better, quantitative understanding of the importance of the ice-emissivity feedback mechanism will benefit both the indigenous population of the Arctic and those regions that may be affected by Arctic change, including the UK. It will directly impact planning decisions made by the relevant national agencies (e.g. DEFRA) relating to sea-level rise (e.g. coastal flood defences) and governmental/inter-governmental policy concerning 'safe' levels of anthropogenic greenhouse gas emissions. There are also clear benefits to improved predictive ability for the insurance industry and for those that might seek to exploit a permanent reduction in Arctic sea-ice (e.g. shipping industry, fishing industry, oil/gas exploration).
Turning to alternative aspects of the proposal, establishing the importance of far infrared radiation (FIR) in terms of both its contribution to polar climate and the unique information contained in this part of the spectrum should strengthen the case for a greater number of dedicated FIR measurements, whether that be from the ground, aircraft, balloon or satellite. For example, there have been recent advances in instrumentation, particularly detector technology, that make a satellite based FIR instrument more feasible than has been the case in the past. UK firms (e.g. Selex UK) are at the forefront of some of these developments and hence the efforts of the ICE-IMPACT team in this area has the potential to benefit both UK industry and science.
More generally, clearly the work will benefit the general public. This will occur through the provision of enhanced information to those making decisions which will impact resilience to change as outlined above, but can also be realised via improved education regarding the fundamental science we will perform. An understanding of the complexity of the climate system, coupled with honest reporting of areas of current uncertainty can lead to improved decision making at the individual level. It can also motivate the climate scientists of the future.
Looking longer-term, a better, quantitative understanding of the importance of the ice-emissivity feedback mechanism will benefit both the indigenous population of the Arctic and those regions that may be affected by Arctic change, including the UK. It will directly impact planning decisions made by the relevant national agencies (e.g. DEFRA) relating to sea-level rise (e.g. coastal flood defences) and governmental/inter-governmental policy concerning 'safe' levels of anthropogenic greenhouse gas emissions. There are also clear benefits to improved predictive ability for the insurance industry and for those that might seek to exploit a permanent reduction in Arctic sea-ice (e.g. shipping industry, fishing industry, oil/gas exploration).
Turning to alternative aspects of the proposal, establishing the importance of far infrared radiation (FIR) in terms of both its contribution to polar climate and the unique information contained in this part of the spectrum should strengthen the case for a greater number of dedicated FIR measurements, whether that be from the ground, aircraft, balloon or satellite. For example, there have been recent advances in instrumentation, particularly detector technology, that make a satellite based FIR instrument more feasible than has been the case in the past. UK firms (e.g. Selex UK) are at the forefront of some of these developments and hence the efforts of the ICE-IMPACT team in this area has the potential to benefit both UK industry and science.
More generally, clearly the work will benefit the general public. This will occur through the provision of enhanced information to those making decisions which will impact resilience to change as outlined above, but can also be realised via improved education regarding the fundamental science we will perform. An understanding of the complexity of the climate system, coupled with honest reporting of areas of current uncertainty can lead to improved decision making at the individual level. It can also motivate the climate scientists of the future.
Organisations
- Imperial College London (Lead Research Organisation)
- Meteorological Office UK (Collaboration)
- National Aeronautics and Space Administration (NASA) (Collaboration)
- Lawrence Berkeley National Laboratory (Collaboration, Project Partner)
- University of Michigan (Collaboration)
- National Institute of Optics (Collaboration)
- National Aeronautics and Space Administration (Project Partner)
- University of Michigan–Ann Arbor (Project Partner)
- Istituto Nazionale di Ottica (Project Partner)
- Met Office (Project Partner)
People |
ORCID iD |
Helen Brindley (Principal Investigator) |
Publications
Murray J
(2016)
The Cirrus Coupled Cloud-Radiation Experiment-II
Palchetti L
(2016)
The Far Infrared FTS for the FORUM Mission
Magurno D
(2020)
Cirrus Cloud Identification from Airborne Far-Infrared and Mid-Infrared Spectra
in Remote Sensing
Bellisario C
(2017)
Retrievals of the Far Infrared Surface Emissivity Over the Greenland Plateau Using the Tropospheric Airborne Fourier Transform Spectrometer (TAFTS)
in Journal of Geophysical Research: Atmospheres
Murray J
(2020)
Retrievals of High-Latitude Surface Emissivity Across the Infrared From High-Altitude Aircraft Flights
in Journal of Geophysical Research: Atmospheres
Warwick L
(2022)
Retrieval of Tropospheric Water Vapor From Airborne Far-Infrared Measurements: A Case Study
in Journal of Geophysical Research: Atmospheres
Saito M
(2020)
Spaceborne Middle- and Far-Infrared Observations Improving Nighttime Ice Cloud Property Retrievals
in Geophysical Research Letters
Description | We have used unique aircraft based measurements of the radiation emitted by snow covered surfaces in the so-called far infrared (FIR: wavelengths between ~ 15 and 100 microns) to show that the emissivity of snow is less than that of a perfect emitter - an assumption commonly made in global climate models. We have compared these measurements to current theoretical estimates and have shown that these are unable to simultaneously match the observations across the full infrared spectrum. We have shown that it is possible to extend observations from the mid-infrared (MIR) to the far-infrared using a statistical approach but that the uncertainties associated with the MIR measurements need to be carefully accounted for. |
Exploitation Route | Our estimates of FIR emissivity can be used by climate modellers to assess the impact on the polar energy budget. We plan to look into this ourselves through the course of this grant (see comments above). Clearly the selection of FORUM opens up a wealth of opportunities for climate science and for industry. |
Sectors | Aerospace Defence and Marine Communities and Social Services/Policy Environment |
URL | https://www.esa.int/Applications/Observing_the_Earth/A_new_satellite_to_understand_how_Earth_is_losing_its_cool |
Description | Provided input to case for FORUM mission, subsequently selected as a European Space Agency Explorer Mission. |
First Year Of Impact | 2016 |
Sector | Aerospace, Defence and Marine,Environment |
Impact Types | Societal Economic |
Description | Aircraft campaign support for FORUM |
Amount | € 399,999 (EUR) |
Organisation | European Space Agency |
Sector | Public |
Country | France |
Start | 11/2018 |
End | 06/2019 |
Description | FORUM Mission support studies |
Amount | € 207,500 (EUR) |
Organisation | European Space Agency |
Sector | Public |
Country | France |
Start | 07/2018 |
End | 03/2019 |
Description | Future Missions/FORUM |
Amount | £769,231 (GBP) |
Funding ID | 4000137153/22/NL/IA |
Organisation | European Space Agency |
Sector | Public |
Country | France |
Start | 12/2021 |
End | 12/2023 |
Title | TAFTS CIRRCREX data |
Description | Calibrated far infra-red radiances measured by the TAFTS instrument over Greenland as part of the CIRRCREX campaign. |
Type Of Material | Database/Collection of data |
Year Produced | 2020 |
Provided To Others? | Yes |
Impact | First estimates of far infrared surface emissivity from high altitude flights. |
URL | https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2020JD033672 |
Description | ICE-IMPACT Team |
Organisation | Lawrence Berkeley National Laboratory |
Country | United States |
Sector | Public |
PI Contribution | We lead the team, providing coordination activities and underpinning scientific exploitation. |
Collaborator Contribution | The partners are working in related fields on modelling and measurement and in instrument design. We exploit some of their measurements and in turn they will use some of our observationally based results to improve their modelling capability. |
Impact | Outputs include participation in Earth Explorer 9 candidate mission FORUM. |
Start Year | 2016 |
Description | ICE-IMPACT Team |
Organisation | Meteorological Office UK |
Country | United Kingdom |
Sector | Academic/University |
PI Contribution | We lead the team, providing coordination activities and underpinning scientific exploitation. |
Collaborator Contribution | The partners are working in related fields on modelling and measurement and in instrument design. We exploit some of their measurements and in turn they will use some of our observationally based results to improve their modelling capability. |
Impact | Outputs include participation in Earth Explorer 9 candidate mission FORUM. |
Start Year | 2016 |
Description | ICE-IMPACT Team |
Organisation | National Aeronautics and Space Administration (NASA) |
Department | NASA Langley Research Centre |
Country | United States |
Sector | Public |
PI Contribution | We lead the team, providing coordination activities and underpinning scientific exploitation. |
Collaborator Contribution | The partners are working in related fields on modelling and measurement and in instrument design. We exploit some of their measurements and in turn they will use some of our observationally based results to improve their modelling capability. |
Impact | Outputs include participation in Earth Explorer 9 candidate mission FORUM. |
Start Year | 2016 |
Description | ICE-IMPACT Team |
Organisation | National Institute of Optics |
Country | Italy |
Sector | Public |
PI Contribution | We lead the team, providing coordination activities and underpinning scientific exploitation. |
Collaborator Contribution | The partners are working in related fields on modelling and measurement and in instrument design. We exploit some of their measurements and in turn they will use some of our observationally based results to improve their modelling capability. |
Impact | Outputs include participation in Earth Explorer 9 candidate mission FORUM. |
Start Year | 2016 |
Description | ICE-IMPACT Team |
Organisation | University of Michigan |
Country | United States |
Sector | Academic/University |
PI Contribution | We lead the team, providing coordination activities and underpinning scientific exploitation. |
Collaborator Contribution | The partners are working in related fields on modelling and measurement and in instrument design. We exploit some of their measurements and in turn they will use some of our observationally based results to improve their modelling capability. |
Impact | Outputs include participation in Earth Explorer 9 candidate mission FORUM. |
Start Year | 2016 |
Description | Contribution to ESA's 'Campaign Earth' blog |
Form Of Engagement Activity | Engagement focused website, blog or social media channel |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Public/other audiences |
Results and Impact | Description of campaign activities in support of the FORUM mission - at the time a candidate for ESA's Earth Explorer 9. The 'Campaign Earth' website is designed to inform the general public about campaigns that are taking place in support of ESA Earth Observation missions. |
Year(s) Of Engagement Activity | 2019 |
URL | http://blogs.esa.int/campaignearth/2019/03/25/flying-for-forum-a-day-in-the-life-of-a-phd-student/ |
Description | Fringe event at Imperial College |
Form Of Engagement Activity | Participation in an activity, workshop or similar |
Part Of Official Scheme? | No |
Geographic Reach | National |
Primary Audience | Public/other audiences |
Results and Impact | Imperial Fringe 'Space Odyssey' event intended for the general public to learn about space related activities at Imperial College. Activities included a poster and instrument stand and public tours to the Imperial Earth Observation Calibration Facility. |
Year(s) Of Engagement Activity | 2017 |
Description | Interview for national news |
Form Of Engagement Activity | A press release, press conference or response to a media enquiry/interview |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Media (as a channel to the public) |
Results and Impact | Interview with BBC News describing FORUM mission after its selection as Earth Explorer 9. |
Year(s) Of Engagement Activity | 2019 |
URL | https://www.bbc.co.uk/news/av/science-environment-49811239/forum-satellite-will-investigate-how-eart... |
Description | Podcast for Naked Scientists programme |
Form Of Engagement Activity | A broadcast e.g. TV/radio/film/podcast (other than news/press) |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Media (as a channel to the public) |
Results and Impact | Podcast recording entitled 'Taking Earth's temperature' for Naked Scientists website/media outlet. Interview based around the selection of FORUM as ESA's 9th Earth Explorer. |
Year(s) Of Engagement Activity | 2019 |
URL | https://www.thenakedscientists.com/articles/interviews/taking-earths-temperature-0 |
Description | UKSA Blog |
Form Of Engagement Activity | Engagement focused website, blog or social media channel |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Public/other audiences |
Results and Impact | Blog describing FORUM mission for non-experts, to coincide with signing of industrial contract. |
Year(s) Of Engagement Activity | 2022 |
URL | https://space.blog.gov.uk/2022/06/28/how-forum-will-improve-climate-change-forecasts/ |