Conveners: Peter Pilewskie, Manfred Wendisch, Hajime Okamoto, Byung-Ju Sohn, Márcia Akemi Yamasoe, Alkis Bais

This session includes keynote lectures from invited speakers on outstanding issues. Confirmed speakers are:

• Christos Zerefos – Academy of Athens, Greece
  Optical Reflections from Ancient Greece
• Tony McNally – ECMWF, United Kingdom
  The use of satellite radiation measurements for forecasting the weather: Past, present and future
• Graeme Stephens – Jet Propulsion Laboratory, U.S.A.
  The shaping of Earth’s climate through the cycles of water and energy
• Ping Yang – Texas A&M University, U.S.A.
  Light Scattering by Non-spherical Atmospheric Particles: Brief History, Recent Advances and Applications
• Manfred Wendisch – Leipzig Institute for Meteorology, Germany
  How field observations can help to constrain models
• Jeremy Werdell – NASA Goddard Space Flight Center, U.S.A.
  Observing the Microscopic Living (and Non-Living) Ocean from Space
• Jennifer E. Kay – CIRES University of Colorado at Boulder, U.S.A.
  Are climate feedbacks linear with carbon dioxide forcing?

Conveners: Iouli Gordon – Harvard & Smithsonian; Eli Mlawer – Atmospheric and Environmental Research Inc.

This session invites papers on radiative transfer (RT) theory and modelling, including studies of molecular radiative properties and their applications in atmospheric remote sensing. The main interest is in applications of these theories and relevant spectroscopic input to satellite, airborne and ground-based atmospheric remote sensing missions. This session welcomes papers on the methods for identifying errors and limits of various RT methods (including reference spectroscopic data) in climate and remote sensing studies. We welcome reports on measurements and theoretical analysis of molecular line parameters and absorption cross-sections including those that employ sophisticated line shape profiles.

Conveners: Ping Yang – Texas A&M University

Light scattering is an important branch of atmospheric physics essential to the implementation of advanced remote sensing techniques and the investigation of the radiative forcings caused by various atmospheric constituents (clouds and aerosols, in particular). This session provides a forum for the presentations of recent advances in electromagnetic scattering, such as the single-scattering properties of nonspherical aerosol particles and ice crystals, and relevant applications to scalar and vector  radiative transfer simulations and the implementations of active and passive remote sensing techniques.

Conveners: Piet Stammes – Royal Netherlands Meteorological Institute; Feng Zhang – Nanjing University of Information Science and Technology, Nanjing, China; Otto Hasekamp – Space Research Organization Netherlands, Utrecht, Netherlands; Jerome Riedi – Laboratoire d’Optique Atmospherique, Lille, France; Yasuko Kasai – National Institute of Information and Communications Technology, Tokyo, Japan.

The theme of this session is remote sensing of the Earth’s atmosphere and surface by satellite, airplane, UAV, and ground-based instruments. Radiation is the common element in passive and active remote sensing of the dynamical state and the physical and chemical composition of the atmosphere. To interpret remote sensing measurements, radiative transfer modelling is needed, and retrieval or inversion techniques have to be developed.

In recent years innovative satellite instruments have been launched, creating new remote sensing capabilities of atmosphere, land and ocean. Further satellites are planned to be launched in the coming years. These include meteorological satellites, environmental satellites, and research satellites. Interpretation and preparation for these new satellite data give a strong  stimulus to development of fast but accurate radiative transfer methods and retrieval and data processing techniques.

We solicit presentations on:

• Ultraviolet, visible, near-infrared and shortwave infrared remote sensing
• Thermal and far infrared remote sensing
• Microwave remote sensing
• Multi-spectral imagery
• Spectrometry
• Polarimetry
• Forward radiative transfer modelling
• Retrieval or inversion techniques, including machine learning
• Calibration and validation
• Research and operational applications.

Conveners: Manfred Wendisch – Leipzig Institute for Meteorology; Roberta Pirazzini – Finnish Meteorological Institute; Zhengqiang Li – Aerospace Information Research Institute, Chinese Academy of Sciences; Gijs DeBoer – University of Colorado; Sebastian Schmidt – University of Colorado

This session invites contributions from atmospheric radiation measurements (irradiances, radiances) across the entire wavelength spectrum (UV, solar, thermal and far infrared). In particular, presentations and posters describing exciting instrument developments, new calibration techniques, and innovative methodologies are called for. Furthermore, papers showing results of long- and short-term ground-based radiation measurements (including networks) are appreciated, as well as of radiation data collected during dedicated field campaigns by airborne radiation instruments (unmanned airborne systems, helicopters, balloons, and aircraft). Contributions describing new findings from recent campaigns and plans for upcoming major observational activities, in which atmospheric radiation devices are involved as a major component, are invited. Also, presentations and posters describing the radiative properties of clouds, aerosol particles, gaseous atmospheric components, and surfaces and related interactions with atmospheric radiation are highly welcome. Contributions describing the outcome of model studies used to interpret the measurements are also highly encouraged.

Conveners: Seiji Kato – NASA Langley Research Center; Martin Wild – ETH Zurich; Norman G. Loeb – NASA Langley Research Center

Understanding the radiation budget is necessary to understand the energy budget of the climate system. In addition, quantifying the variability of the radiation budget and understanding the cause of the variability are essential in understanding how the energy budget of the climate system changes in response to increasing radiative forcing. The goal of this session is to bring together observational and modeling studies of the Earth radiation budget and radiative forcing at the top-of-atmosphere, surface, and atmosphere at a wide range of temporal and spatial scales. Description of algorithms to produce radiation budget data products, uncertainty estimates, and evaluation of modeled estimates with observations, as well as future radiation budget mission concepts are a further scope of the session. In addition, studies that aim at quantifying radiation budget variability and understanding the relationship to surface, atmospheric and cloud properties, as well as the connection to the variability of large scale dynamics and water cycle are of interest. In addition, studies focusing on the relationship between the natural variability of the radiation budget and the radiation budget change at a longer time scale are encouraged. Aerosol direct and indirect radiative effect and forcing, cloud radiative effects, and comparison of modeled and observational estimates are also welcome.  

Conveners: Jhoon Kim – Yonsei University; Allen Huang – University of Wisconsin-Madison ; Hua Zhang – China Meteorological Administration

The radiative process is a key element in understanding and observing weather, climate, and environment. Session papers are solicited for subjects, key issues, and emerging applications that are of interest but not limited to:

1. The use of radiation measurements to improve weather, climate & environment monitoring
2. Radiative processes in weather, climate and environment, and their consequences (e.g., cloud‐climate interactions, aerosol‐chemistry‐climate interactions, atmosphere‐ocean interactions, cloud-aerosol impact on trace gas retrieval)
3. Global and regional radiation climatologies and reference solar spectra

4. Other topics such as:

• • Design, development, and implementation of future weather/ climate/  environment sensors
  • National and international future weather/ climate / environment research program and initiative
  • Other general studies on future weather/ climate / environment, such as those on the data analysis method, data quality, new data sets, observation systems
  • Improvements in future weather/ climate / environment forecasts as a consequence of improved parameterization of the radiative process guided by theoretical knowledge and
  • Variations in radiation, hydrologic and other climate variables on timescales ranging from seasonal to interannual, and to interdecadal, with implications for climate
  • Impact of clouds, aerosol, greenhouse gases, and solar forcing on Earth’s climate change, including comparisons of simulations with observations
  • Growing needs for the long term high-quality data records
  • Emerging applications in renewable energy management, hazard monitoring, carbon cycle, pollution, and other real‐time weather/environment events
  • Recent Artificial Intelligence (AI) advancement for weather/ climate/ environment monitoring and forecasting

Conveners: Ann R. Webb – University of Manchester; Julian Gröbner – Physikalisch-Meteorologisches Observatorium Davos / World Radiation Center; Andreas Kazantzidis – University of Patras

The session focuses on the ultraviolet part of the solar spectrum and welcomes contributions on all aspects of solar UV radiation, including (but not limited to):

• Measurement of UV radiation from ground or space, including new instruments, analysis techniques or datasets
• UV radiation modelling
• Interaction between UV radiation and the atmosphere (clouds, ozone, aerosols, atmospheric chemistry), oceans and cryosphere
• UV radiation climatology and climate change
• Effects of UV radiation on the biosphere, including human health

Conveners: Jeremy Werdell – NASA Goddard Space Flight Center; Hiroshi Murakami – Japan Aerospace Exploration Agency; Ewa Kwiatkowska –EUMETSAT; Michael Twardowski – Florida Atlantic University

Measurements of ocean color and the optical properties of aquatic environments have revolutionized our understanding of Earth’s oceans, coasts, and inland water bodies over the past four decades.  Ocean color remote sensing utilizes the intensity and spectral variation of visible light scattered upward from beneath the ocean surface to derive aquatic optical properties and concentrations of biogeochemical constituents within the surface layer. Recent years have seen a sharp increase in the availability of air- and space-borne instruments to measure aquatic optical properties, as well as substantial advancements in detector technology, radiative transfer modeling, and in situ observing systems. This session provides an opportunity to showcase innovations and results that contribute to these advances. Presentations highlighting air-borne, space-borne, laboratory, and in situ instruments and observing systems, as well as in-water and remote-sensing radiative transfer analyses are all welcome.

Conveners: Dimitris Balis – Aristotle University of Thessaloniki; Klairie Tourpali – Aristotle University of Thessaloniki; Alcide Giorgio Di Sarra – Italian National Agency for New Technologies; Michaël Sicard – Universitat Polytecnica de Catalunya

This session aims at scientific contributions on radiative processes and applications specifically for the Mediterranean. This region, recognized as a climate change hot spot, is one of the most responsive and vulnerable regions to environmental change, with conditions conducive for photochemical air pollution and high concentrations of aerosol particles from natural (desert dust, marine, volcanic) and anthropogenic sources.

It includes:

• Effects of natural and anthropogenic aerosols on solar radiation at the Earth’s surface, with emphasis on desert dust and wildfires, using in-situ and remote sensing observations and modelling.
• Effects of air pollutants on solar radiation and photochemistry in the troposphere and the surface.
• Radiative forcing calculations and projections under different climate scenarios.
• Regional climate modelling studies focusing on radiative effects in the Mediterranean