Fabio Giulio Tonolo

A Low-Cost Mobile Mapping System (LCMMS) for field data acquisition: a potential use to validate aerial/satellite building damage assessment

Among the major natural disasters that occurred in 2010, the Haiti earthquake was a real turning point concerning the availability, dissemination and licensing of a huge quantity of geospatial data. In a few days several map products based on the analysis of remotely sensed data-sets were delivered to users. This demonstrated the need for reliable methods to validate the increasing variety of open source data and remote sensing-derived products for crisis management, with the aim to correctly spatially reference and interconnect these data with other global digital archives. As far as building damage assessment is concerned, the need for accurate field data to overcome the limitations of both vertical and oblique view satellite and aerial images was evident. To cope with the aforementioned need, a newly developed Low-Cost Mobile Mapping System (LCMMS) was deployed in Port-au-Prince (Haiti) and tested during a five-day survey in February–March 2010. The system allows for acquisition of movies and single georeferenced frames by means of a transportable device easily installable (or adaptable) to every type of vehicle. It is composed of four webcams with a total field of view of about 180 degrees and one Global Positioning System (GPS) receiver, with the main aim to rapidly cover large areas for effective usage in emergency situations. The main technical features of the LCMMS, the operational use in the field (and related issues) and a potential approach to be adopted for the validation of satellite/aerial building damage assessments are thoroughly described in the article.

Rapid Mapping: geomatics role and research opportunities

In recent years an increasing number of extreme meteorological events have been recorded. Geomatics techniques have been historically adopted to support the different phases of the Emergency Management cycle with a main focus on emergency response, initial recovery and preparedness through the acquisition, processing, management and dissemination of geospatial data. In the meantime, the increased availability of geospatial data in terms of reference topographic datasets, made available by authoritative National Mapping Cadastre Agencies or by Collaborative Mapping initiatives like OpenStreetMap, as well as of remotely sensed imagery, poses new challenges to the Geomatics role in defining operational tools and services in support of emergency management activities. This paper is mainly focused on the role of Geomatics in supporting the response phase of the Emergency Management cycle through Rapid Mapping activities, which can be defined as “the on-demand and fast provision (within hours or days) of geospatial information in support of emergency management activities immediately following an emergency event” (source: European Union, http://emergency.copernicus.eu/mapping/ems/service-overview). Management of geospatial datasets (both reference and thematic), Remote Sensing sensors and techniques and spatial information science methodologies applied to Rapid Mapping will be described, with the goal to highlight the role that Geomatics is currently playing in this domain. The major technical requirements, constraints and research opportunities of a Rapid Mapping service will be discussed, with a specific focus on: the time constraints of the service, the data quality requirements, the need to provide replicable products, the need for consistent data models, the advantages of data interoperability, the automation of feature extraction procedures to reduce the need for Computer Aided Photo Interpretation, the dissemination strategies.

Remote Sensing Role in Emergency Mapping for Disaster Response

In recent years, due to an increasing number of extreme meteorological events potentially related to climate change, a growing attention has been paid to the operational use of satellite remote sensing applied to emergency management applications. This is mainly due to the large and timely availability of different types of remotely sensed data—as well as geospatial information acquired in the field—which may be potentially exploited in the different phases of the disaster management cycle. This paper is mainly focused on the use of remotely sensed data in emergency mapping applications supporting the crisis response phase, including natural disasters as well as humanitarian crisis. The main relevant initiatives related to emergency mapping operational services will be briefly described. For the main disaster types the suitable imagery, their relevant technical features and the main processing techniques generally adopted in an operational framework will be described. Known limitations of a satellite-based approach will be described and potential complementary geomatics techniques (including emerging technologies) to overcome the aforementioned limits will be discussed.

Multitemporal SAR coherence analysis: Lava flow monitoring case study

This paper is focused on an operational case study related to the adoption of a Multi-Temporal Coherence (MTC) color composite approach to support monitoring activities of volcanic eruption events. A specific case study related to the volcanic eruption in Fogo Island (Cape Verde), which started on late November 2014 will be presented and discussed. A MTC analysis based on data acquired by the COSMO-SkyMed SAR satellite constellation of the Italian Space Agency is describe in details. The thematic accuracy of the MTC based analysis is assessed exploiting as comparison data lava extents derived by very high resolution satellite imagery acquired in the same period.

Damage assessment exploiting remote sensing imagery: Review of the typhoon Haiyan case study

The present paper aims to review the role satellite remote sensing played during the response phase to the largest (in terms of mortality) natural disaster occurred in 2013, i.e. the tropical typhoon Haiyan that struck the Philippines in November 2013. The outcomes of a thorough analysis of the emergency mapping products (about 750 maps) released in the aftermath of the event and in the following weeks are analyzed, with the goal to derive information and statistics on the main product types, the underlying datasets and the input data. Focusing on the damage assessment maps based on satellite data, operational tests on satellite imagery semi-automated classification techniques aimed at automatically extract damaged buildings will be described and discussed.

Building damage assessment scale tailored to remote sensing vertical imagery

ABSTRACT Damage assessment from very high resolution (VHR) remote sensing imagery plays a fundamental role in the delineation of the impact caused by catastrophic events. To date internationally accepted standard guidelines on how to assess damages to building using vertical imagery have not yet been developed. This study therefore proposes a building damage scale – and related interpretation guidelines to be operationally adopted as a standard by the main stakeholders – tailored to analyses based on VHR remote sensed vertical imagery. Preliminarily, some of the damage scales used for building damage assessment by the main satellite-based emergency mapping services have been analysed and discussed. A quantitative thematic accuracy analysis based on the open accessible crisis datasets related to the earthquake occurred in Central Italy in August 2016 has been carried out. The results highlight that by using VHR remotely sensed images it is not possible to directly apply damage classification scales addressing slight structural damages (e.g. the lowest grades proposed by EMS-’98). The paper demonstrates that using different damage classes and detailing the interpretation guidelines with operational examples is essential to increase the thematic accuracy of the analysis.

Satellite SAR interferometric techniques in support to emergency mapping

ABSTRACT This paper investigates the potential of Synthetic Aperture Radar (SAR) interferometry in the field of emergency mapping, assessing its suitability for both rapid mapping, aimed at supporting the immediate response phase after a disastrous event, and risk mapping, addressing risk prevention and mitigation activities. The conventional Differential Interferometric SAR technique (DInSAR) and the two currently available multi-temporal interferometric approaches, i.e. Permanent Scatterers (PS) and Small BAseline Subset (SBAS), have been evaluated focusing on the main emergency mapping requirements, namely crisis information product types, availability of optimal input data, requirements in terms of auxiliary data, processing time and expected accuracy. The aforementioned investigations have been carried out exploiting the European Space Agency (ESA) C-band Sentinel-1 mission, characterized by a free, full and open data policy. Therefore, this paper will not assess different SAR sensors and their different technical specifications, e.g. wavelength and space resolution. Representative results are presented and discussed with the aim to describe the possible interferometric product types in specific emergency mapping scenarios.