Fundamental aspects of cloud physics as the basis for cloud
seeding:
Studies on Cloud condensation nuclei, ice nucleation, aerosol-cloud-precipitation
interactions, and secondary ice production in different global environments
are invited. This may include laboratory, field measurements, or numerical
simulation studies. This session deals with the scientific processes that are
the foundations of rain enhancement programs and may present cloud
formation through warm and cold cloud processes. The contributions may
include theoretical studies, laboratory studies, numerical simulations and
reports on the field experiments.
Precipitation enhancement studies in deep convective clouds:
The session may involve weather modification strategies, field experiments,
laboratory studies, numerical modelling of deep convective clouds, including
field campaign reports, long-term studies on randomization experiments,
AI/ML based models, etc. Both hygroscopic and glaciogenic seeding methods
are included.
Precipitation enhancement studies in shallow/orographic clouds:
Winter orographic cloud seeding studies are done extensively. Specific topics are
relating to long-term weather modification experiments, numerical simulations,
radar-based evaluations, generating cells, etc. The session can include
different aspects of stratiform cloud seeding or shallow cloud seeding, either
with glaciogenic or hygroscopic seeding.
Hail mitigation, fog or rain suppression:
The session includes hail suppression studies and evaluations, the
suppression of fog as well as rain, the latter of which transitions to weather
management studies. Hail suppressions are done with glaciogenic seeding
agents and this session will discuss the major experiments and results from
hail suppression studies.The topics may also cover the seeding impact and
physical evaluations of hail suppression. The polarimetric radar observations
play a key role in the evaluation. The session may also discuss the dynamic
and static cloud seeding. The results on seasonal evaluations of hail
suppression studies and documented evidence are invited The electrical
properties of storms and how seeding impacts these aspects are also of
interest. Results on the hail storms with hygroscopic seeding may also be
discussed.
Warm and cold fog suppression studies are conducted around the world,
however are more complex due to complex boundary layer processes. The
documented results on demonstrated field experiments and synthesis of state
of knowledge in the field may be considered.
Hydrological processes, impacts, and assessments
The session may report feasibility or impact studies for cloud seeding using
hydrological modelling. The climatology, suitable/seedable clouds statistics,
optimum experiments and designs for best outcome from seeding, ensemble
model approaches may also be discussed.
Broader applications/hazard mitigation (Eg. Bushfire/forest fire or
avalanche mitigation, cyclone or typhoon mitigation, etc.)
Fire events cause significant economic, life and livelihood losses. In several
instances, dry weather and also lightning cause fire events. The strong and
turbulent winds indeed help in the spreading of fire. One way of weather
modification is to try to reduce the electric fields within thunderstorms and to
suppress the lightning discharges. The methods used for this weather
modification activities, efficacy, and the science of seeding methods will be
discussed. Numerical modelling efforts on the fire events and mitigation are
also welcome. Numerical studies or other exploratory studies on avalanche
mitigation, cyclone/typhoon mitigation are also included in this session.
The fire events, especially biomass burning, different agricultural practices
and industrial activities make inadvertent modifications in the weather and
also influence precipitation. The session will seek contributions from urban
studies and other inadvertent weather modification studies, specific to the
aerosol-cloud-precipitation interactions. The air quality may be impacted and
the visibility/fog conditions can occur. The session will seek contributions on
all these topics.
Emerging technologies or new methods for weather modification
The emerging technologies for weather modification research or applications
are widespread, and include (but not limited to): topics utilizing AI/ML-based
approaches, digital twin, balloon-based seeding techniques, ground-based
generators, automated seeding drones and use of unmanned aircraft systems
(UAS), new seeding agents, such as nanoparticles, charged seeding
particles, etc. In addition, observational technologies such as the use of
phased array radars or other continuous monitoring radars are also emerging.
The use of state-of-the-art scanning and observing systems, new cloud and
precipitation probes, and other instruments may also be described.
Weather forecasting, and nowcasting Decision Support Systems
Decision support systems are part of many weather modification experiments.
This may include weather forecasting and nowcasting. The use of radar
observations in weather modification experiments and new methods such as
tracking the storm initiation, possible development of secondary storms, how
the decision support systems can be improved with new emerging techniques
can be discussed.
Ethical, Legal and Social Issues (ELSI) topics
This session will discuss societal, ethical, and legal aspects of weather
modification. The measures undertaken prior to operational weather
modification will be discussed. The environmental impacts, extra area effects
of seeding, any evidence of impact from the ongoing or past experiments,
operational projects, long-term impacts on the ecosystem or biota, and related
topics may be presented.
Climate intervention/Marine Cloud Brightening
Anthropogenic impact on weather and climate is discussed in this section.
Aerosols, land use, or other ways of climate interventions are discussed in
this session. Both the continental and marine projects; especially the cloud
brightening projects and summaries of such projects are invited. Specific
papers on cirrus cloud thinning, stratospheric aerosol injection modelling
experiments, and studies and simulations of marine cloud brightening are
invited.
Stakeholder/policymaker/public engagement and communication
WMO has a statement on the weather modification aspects, and it is desirable to
have reporting of the weather modification projects to WMO for records. WMO also
recommends following certain guidelines before any weather modification project.
The session will share such knowledge through the WMO Expert Team with
stakeholders/policy makers.
Effective engagement with policymakers and stakeholders is critical to conducting
weather modification research and operations. This session invites topics related to
methods and approaches for engagement with policymaker, stakeholder, and other
public communities. In addition, topics on communication approaches, issues, and
challenges, as well as educational efforts and challenges encountered.
