Satellite skills and knowledge for operational meteorologist

Above anvil cirrus plumes (AACPs) have been established in the scientific literature since 1980s. Recent improvements in the temporal and spatial resolution of the satellite data brought back attention to their potential use as an indicator of severity of convective storms. In 2018, we have identified 26 days, where damaging hail reaching at least 5 cm, causing significant economic or societal impact was reported to the European Severe Weather Database. For the selected hailstorm days, where rapid-scan imagery with 5-minute temporal resolution was available, we identified 29 very large (>= 5 cm) hail producing storms. 25 of these hailstorms did show an AACP, but only 12 of these plume producing storms could be clearly identified using the visible imagery. The range of lead time of the AACP appearance to the first hail report was very large and in about half of the cases, the plume occurred only during or after the time of the first large hail report. Due to the limited number of cases, the main purpose of the presentation is, rather than drawing conclusions, to open a discussion on the operational usability of AACPs in warnings for convective storms.

Go to Webcast...

Lecture slides...

Many severe meteorological events occurred in Europe during the last decade and caused casualties and damages to the historical heritage and natural environment. Protection of civilians and safeguard of the territory are the kay mandates of a civil Protection (CP) agency. This is achieved through activities that mitigate hydro-meteorological risks, such as flooding and droughts. European CP agencies, supported by meteorological and hydrological institutes, aim to assess risk scenarios, to monitor and supervise events and risk levels, providing early warning to National and local authorities.
Near real time accurate estimations of hydrological variables such as precipitation and soil moisture are invaluable to the CP agencies, enable them to issue early warnings and plan for disaster relief at the local level.
Besides measurements of key hydrological variables by ground-based instruments, often affected by a limited spatial coverage, advanced satellite-based precipitation and soil moisture products developed within different international programs as H SAF, are available and accessible to users in near-real time.
In this study, recent severe meteorological events are selected in order to understand how the main satellite product characteristics, i.e. accuracy, spatial pattern and resolution, update frequency and latency, impact the efficiency of a hydro-meteorological early warning system at a local level in an operational framework.

Go to Webcast...

Lecture slides...

Large amount of ice particle may cause erroneous aircraft probe measurement and damage aircraft engines. The ice crystals are generally located near cores of deep convection and associated cirrus anvils, at high altitude and in tropical areas. The understanding of the phenomena and its forecast are a key issue for aviation. There are several methods to detect clouds associated with ice crystal icing: MSG-CPP High IWC Mask, DARDAR, PHIWC, Alpha, RDT(detects and tracks convective systems).

A series of fields experiment in tropical regions have been conducted separately or conjointly by HAIC and HIWC projects. During HAIC campaigns, RDT has been provided on an operational basis through dedicated MétéoFrance processing chains. Qualitative and quantitative studies provided reasonably good results, especially in terms of probability of detection.

A new day-time attribute (adapted from MSG-CPP High IWC Mask algorithm) has been implemented in RDT v2016. Now RDT is produced globally by using five geostationary satellites, which in turn increased operational applications. New generation of satellites and the feedback on products performance will help to improve retrieval of the hazard and to define future research fields.

Go to webcast

Lecture slides

Current generation geostationary satellites are observing convection that is hazardous to aviation at increasingly high spatio-temporal detail. In recent years, commercial and research aircraft have collected automated turbulence and cloud ice water content observations that can be used to better understand exactly where within deep convection the turbulence and icing conditions are typically occurring. Ground-based weather radar and severe weather reports also identify locations of hail, downburst wind, and tornadoes. Research conducted at NASA Langley Research Center (LaRC), in collaboration with a number of U.S. and international partners, has resulted in geostationary-based analyses and automated detection algorithms that can denote where turbulence, icing, and severe weather conditions are likely. These methods are applicable to any geostationary visible and IR imager across the globe and therefore can be used to map these weather hazards in nearreal time, a capability that is especially valuable over regions without weather radars and other conventional observations of aviation hazards.

Go to webcast

Lecture slides

Two new satellite-derived products related to turbulence analysis have been developed recently in the frame of the Nowcasting-SAF. The first product (ASII-GW”Automatic Satellite Image Interpretation – Gravity Waves”) objectively detects grating patterns in the water vapor 7.3 imagery which point to the presence of gravity waves. The second product (ASII-TF “Automatic Satellite Image Interpretation – Tropopause Folding”) identifies the location of tropopause folds from satellite and NWP data. The algorithm is based on the logistic regression method.

In this presentation, we will talk about the selected algorithms and present cases from the official Nowcasting-SAF validation reports (to be released shortly) to illustrate the product performance.

Go to webcast

Lecture slides Jann

Lecture slides Andreas

Clear air turbulence (CAT) is the term for medium- or high-level turbulence in regions with significant wind shear. CAT is an important factor for the aviation safety.

In the first part of the presentation, I will show you typical parts of CAT in relation with the 300 hPa geopotential analysis. Furthermore you get an overview to the correlation between CAT and characteristic cloud patterns in satellite images. In many cases satellite images provide the first clue or a confirmation for the presence auf CAT.

The second part is dedicated the forecast of CAT in Deutscher Wetterdienst (DWD) with the ICON model. DWD has been applying a forecast method based on Eddy Dissipation Rate (EDR). This real property of atmospheric turbulence is the main sink term of Turbulent Kinetic Energy. In a case study you will see the typical working process in practice with consideration of the model output, typical cloud pattern in satellite image and the use of the conceptual model and the structure of geopotential field.

Go to webcast

Lecture slides

Since the late 1970's earth-orbiting satellites have been able to observe the weather around the globe and provide quantitative information on cloud movements. These data have proved extremely valuable for tracking volcanic ash clouds and more recently allowing quantitative information on volcanic ash column amounts and also on SO2 gas - another potential hazard to aviation. Notable incidents between commercial aviation and ash clouds, several in Indonesia and Alaska, have occurred during the satellite era (~1960's onwards). The talk will cover methods used to identify, quantify and monitor volcanic ash clouds and frame this in the context of the potential hazard.

Go to webcast

Lecture slides

Polar Lows can be seen as small Arctic hurricanes, and they have a severe impact on shipping and coastal communities in Scandinavia. They are most common in the Barents Sea and the Norwegian Sea, but are also known to occur in the central North Sea and surrounding coastal areas. Polar lows are the most intense type of wintery convection weather phenomenon in this area. Thus, a familiarity with Polar Lows will also increase our ability to forecast the more common snow shower events in the winter season. This talk will present some facts on Polar Lows, how they are forecasted, and give examples of interpretation of satellite imagery.

Go to webcast

Lecture slides

Due to the Azores geographical location, this archipelago is occasionally affected by strong Extratropical cyclones and Tropical cyclones. Extratropical cyclones are more frequent in winter and are often associated with strong winds, heavy precipitation and heavy waves which can be damaging and contribute to social and economic distress. Tropical cyclones, on the other hand occur mostly in September and October and in the past have caused loss of lives and property damage. Forecasting this type of systems is very challenging, mostly because a small variation in path can cause large difference in the impacts. This talk presents some tropical and extratropical cyclones that affected the Azores and also the challenges that forecasters face in this situations.

Go to webcast

Lecture slides

The NOAA Ocean Prediction Center (OPC) is responsible for weather warnings and forecasts for the western North Atlantic and eastern and central North Pacific Oceans. The oceans remain relatively data sparse for observed conditions. To compensate, OPC has successfully used winds from scatterometers and wave heights from altimeters to better understand and predict hazardous conditions over the waters of responsibility. Weather forecasting challenges for large ocean areas will be discussed along with the application of satellite winds and waves.

Go to webcast

Lecture slides

The Mediterranean tropical-like cyclones are intense sub-synoptic maritime lows with strong winds, axisymmetric warm-core structure and tropical cyclone features, such as a cloud-free eye and spiral deep convection. They are frequently referred to as medicanes (MEDIterranean hurriCANES) due to their resemblance to tropical cyclones. Despite their low frequency (of about 1.1-1.6 systems per year), medicanes constitute a serious natural hazard to life, property and the environment of the coastal regions of the Mediterranean basin and the Black Sea. Their accurate prediction is a challenge for the numerical weather prediction models. This presentation includes some past cases of medicanes, the description of their structure and characteristics, criteria that are used to define them, the development mechanisms, climatology, consequences and finally a detailed case study of medicane Qendresa (November 2014).

Go to webcast

Lecture slides

Altimeter data have been used to produce maps of sea surface height, geostrophic velocity, significant wave height and wind speed. This information is of proven use to mariners as well as to the scientific community. Uses of the data include commercial and recreational vessel routing, ocean acoustics, input to geographic information systems developed for the fishing industry, identification of marine mammal habitats, fisheries management and monitoring ocean debris. Such information is accessible in near-real time (within 3 to 48 hours) and to improve weather forecasting models by assimilation. 25 years of data makes it possible to study the whole ocean or regional areas for offshore industries or navigation. In hurricane studies altimetry measures very high waves and strong winds, but also helps identify sea surface height anomalies which can be used as proxies of the warm currents - hurricanes energy source. The lecture will describe how altimeters work, how data is used for everyday marine forecasting at NOAA and assimilation, devoteting special attention to data accuracy and limitations.

Go to webcast

Lecture slides