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Space Weather Atmosphere Model and Indices

Periodic Reporting for period 1 - SWAMI (Space Weather Atmosphere Model and Indices)

Reporting period: 2018-01-01 to 2018-12-31

The SWAMI project shall aim to provide an improved and comprehensive representation of the neutral atmosphere from the surface to 1500 km altitude by developing the new MOWA model, which is based on a coupling between existing models that represent different parts of the near-Earth space environment, and by exploiting new atmospheric and geomagnetic data. New high-cadence geomagnetic indices will be developed and used to drive the model, enabling accurate phasing of storm events. The models to be used in this project are already used operationally, or are close to operational, and thus the outcomes of the project will provide a pathway to improved space weather services, in particular for operators of low Earth orbit satellites. The overarching objective is therefore to give Europe a strategic advantage in orbit prediction through thermosphere modelling, associated user services for launch, LEO-operation, conjunction analysis, re-entry and other relevant applications including space debris services, essentially as a result of the new space weather science that will be enabled thanks to the model’s estimations of mean state and variability notably in the re-entry region, as well as new space weather science not limited to the neutral atmosphere thanks to high-cadence Kp.

ESA is currently implementing phase II of its Space Situational Awareness Space Weather System (and Phase III is being planned). This is built around five Expert Service Centres covering the domains Solar Weather, Ionospheric Weather, Space Radiation, Geomagnetic Conditions and Heliospheric Weather; The phase II project P2-SWE-II is currently running with the participation of all the SWAMI partners. This project aims at producing a prototype atmospheric neutral density forecast service for satellite users and uses forecasts based on DTM. This decision was made after a review of all available models at the start of the P2-SWE-II project, which concluded that the DTM was the best available model, but also that physics-based models, while potentially very useful, did not cover the altitude range for which P2-SWE-II forecasts are required. Therefore, our project will strengthen ESA’s Space Weather System by providing a model, that covers the required altitude range but also by developing high-cadence geomagnetic indices and improved predictions that will outperform existing prediction algorithms. High cadence geomagnetic index values and forecast will be available for integration into the Geomagnetic Conditions Expert Service Centre.
The three main objectives of SWAMI are listed below:

OB1. To develop a model of the whole atmosphere (MOWA) with a science as well as operations-focused approach. Two existing models of the atmosphere, the UM and the DTM, will be extended and blended to produce this unique new whole atmosphere model, which shall provide estimates of both climatology and space weather variability. The model will be validated against observations and other models. An operational tool for satellite re-entry and launch applications shall be developed based on the whole atmosphere model, the MOWA Climatological Model (MCM) with a specification guided by consultation with relevant users.

OB2. To provide new high-cadence geomagnetic Kp-indices, including its nowcast and predictions to be used in the UM and DTM. These products are equally useful for a wide range of space weather services that rely on rapid geomagnetic activity specification.

OB3. To develop steps, including provision of software, model output, or data sharing facilities, to transition the improved model system into operations. A set of acceptance criteria, for example regarding robustness of model code, or near-real-time processing of data and delivery of forecasts, shall be defined and should be met to ensure that the model system can be considered ready for operational use.
Inital extension of UM from a upper boundary of 85 km to one of ~150-170 km has started. A relaxation to climatological temperature was included to provide a realistic basic state to test developments to the UM radiation, chemistry and dynamics. The UM now produces simulations up to 100 km altitude, and new versions with lids at 120 km and 130 km are being set up and tested as part of our incremental progress towards the target lid of 150-170 km. regarding radiation scheme developments, non-local thermodynamics equilibrium (non-LTE) code has been written and tested in standalone mode and is now being incorporated into the full UM. The non-LTE code for the infrared part of the spectrum is nearly readyy. The UM radiation code is also being extended to the far and extreme ultraviolet (UV) we have developed a low resolution (1nm) configuration to calculate radiative fluxes from 1 to 320nm, and discussed the requirements for photolysis rates to be supplied for the extended UM chemistry scheme. we have coded a new treatment of spherical geometry for diffuse fluxes (solar and thermal) to compliment the existing treatment of spherical geometry for the direct solar beam and included significant speed improvements for the treatment of minor gases under spherical geometry which should allow for the inclusion of all species required for photolysis calculations. We are also starting to implement a molecular diffusion and viscosity scheme which will be important in damping wave amplitudes above around 130 km and will be important in ensuring UM stability up to 150-170 km. We are currently on track to meet D2.3 in M18 - as a minimum at this time the UM should be stable up to at least 120 km and include non-LTE radiation and some of the UV and associated chemistry developments, though it is possible that the molecular diffusion scheme shall be available instead of, or in addition to, these developments.
The construction of a first DTM update with new density data, was completed with a few months delay due to unavailability of data. The data were edited and preprocessed more accurately, and consequently internal biases could be determined more accurately. Finally, the model was constructed with the database available in August 2018. The model is less biased and more precise than DTM2013, even if the gain is modest.
Task 3.1 was completed. User survey results were presented and conclusions are included in deliverable D3. Task 3.2 is ongoing without delays. The datasets of Hp90, Hp60, Hp30, ap90, ap60 and ap30 are delivered and will be evaluated and updated during Task 3.4. Task 3.3 is ongoing without delays. A solar wind and Kp database have been built up. The models can be trained independently for different forecast horizon, for short and long-term forecast. Task 3.4 the evolution of Hp indices and the development of an automatized real-time 3H-cadence Kp forecast system is started. This system will be developed further during the second year of the proposal and extended to the high cadence Kp forecast as well.
The work done in the WP4 was focused on understanding the system and gathering the user requirements in order to make the transition to operations
This is the first year of the project life time. The progress beyond the state of the art is not evident at this moment becuase is work in progress. For more details about the progress of the work, please see the work performed during the year.