2.1 Volcanic ash cloud
transport
Submarine eruptions are volcanic eruptions that occur underneath the
water’s surface. Due to hotspots, these eruptions can occur near
constructive edges, subduction zones, and within tectonic plates.
Throughout geological history, explosive submarine eruptions have
occurred in a variety of submarine environments. The accompanying
deposits indicate that the eruption of fractured magma-seawater mixes
forms ascending flows that eventually feed an undersea flow and fall
deposits. Deposits from explosive submarine eruptions have been reported
1-4 km below the surface in the deep sea, with both flow and fall
deposits ranging several kilometres over the seafloor. However, there is
no precise information about ”submarine volcano cloud transport”
available. Yet, based on known data on undersea eruptions using HYSPLIT
models, it can be concluded that volcanic ash is transported through
water during a submerged eruption in the same way as it is transported
through air during an aerial eruption. The difference would be that it
would be transported through water rather than the atmosphere.
In the atmospheric sciences field, the HYSPLIT model is a frequently
used atmospheric transport and dispersion model. The model replicates
the dispersion and trajectory of chemicals carried and diffused through
our atmosphere on local to global dimensions. It is intended to
facilitate a wide variety of simulations concerning the movement and
dispersion of pollutants and dangerous compounds in the atmosphere. Data
acquisition delay varies depending on the sensor and method utilized for
real-time monitoring of volcanic ash clouds. The NOAA/CIMSS Volcanic
Cloud Monitoring website, for example, provides near-real-time
processing of multiple geostationary and low-Earth orbit satellites that
cover a large portion of the globe. The delay period for using CATS
near-real-time lidar measurements to monitor volcanic ash clouds is
around 3-6 hours. The use of DB/DR data processing might eventually
lower the temporal lag for day-night monitoring of volcanic
SO2 and ash clouds. Nevertheless, there is no universal
number for data acquisition latency because it is affected by several
aspects such as the type of sensor, technique, and processing involved.
The utilisation of GEO satellite data is necessary for the early
identification and tracking of volcanic ash plumes and cloud movements.
Volcanic eruptions may now be predicted using thermal infrared remote
sensing technologies. Nevertheless, there is no information on the
typical latency time for monitoring volcanic ash clouds utilizing GEO
satellite data or thermal infrared remote sensing technologies. Early
detection and tracking of volcanic ash plumes and cloud trajectories
requires the use of GEO satellite data. The principal observables of
volcanoes include deformation, surface alteration, gas emissions,
temperature anomalies, and ash clouds. Deformation has been proven to
precede volcanic eruptions in terms of predicting. Because of
high-temporal-resolution geostationary and polar-orbiting meteorological
satellite data, gas emissions and thermal anomalies may be detected in
near-real time. Yet, because of their fluctuating composition and size
dispersion, ash clouds are more difficult to observe. Even with a lag of
one hour owing to propagation time, worldwide infrared monitoring can
offer timely information to Volcanic Ash Advisory Centres (VAAC).
Observational data from satellite remote sensing networks are crucial in
estimating the ash cloud’s 4D dispersion. In this paper, we use HYSPLIT
modelling system to monitor the ash cloud trajectories during the event.
To summarize, several factors influence the latency time for monitoring
volcanic ash clouds. They include satellite data difficulties such as
delay and limited access to pictures. Mesoscale scanning can greatly
reduce latency, while distant sensing networks play an important role in
identifying the 4D dispersion of the ash cloud.