On July 23, 1972, the Earth Resources Technology Satellite (ERTS-1), later renamed as Landsat, was launched into orbit. This was the first civil satellite doing Earth Observation over our planet Earth. Coincidentally, also in 1972, the World Heritage Convention was agreed upon at the United Nations Educational Scientific and Cultural Organization (UNESCO). The 1972 World Heritage Convention concerning the Protection of the World Cultural and Natural Heritage developed from the merging of two separate movements: the first focusing on the preservation of cultural sites, and the other dealing with the conservation of nature. The most significant feature of the 1972 World Heritage Convention is that it links together in a single document the concepts of nature conservation and the preservation of cultural properties. The Convention recognizes the way in which people interact with nature, and the fundamental need to preserve the balance between the two.
Since the end of the 1990’s, the concept of the potential of using Earth Observation data and technologies to support Natural and Cultural heritage sites has been on the table of discussions.
This paper will present the current state-of-the-art as far as Earth Observation supporting Natural and Cultural heritage. The main concepts described in this paper emerge from the overall experience gained during the fifteen years of managing and implementing the European Space Agency (ESA) and UNESCO Open initiative on the use of space technologies to support World Heritage sites: “From Space to Place”, as well as a series of further additional activities supporting heritage sites implemented afterwards.
Although the World Heritage Convention deals with Natural and Cultural heritage under the same framework Convention, the issue of EO supporting Natural and Cultural Heritage has to be addressed as dealing with two different concepts of Heritage, therefore through a separated approach. The needs and requirements of Natural heritage are different to those of the Cultural heritage domain. The main know how to manage Natural heritage is basically under the “hat” of for example, a park ranger, while the expertise to manage a Cultural heritage site, depending on the type of cultural heritage site, might be for example under the “hat” of an archaeologist. This implies per se that the chain of activities for the management, conservation, monitoring and dissemination of a Natural heritage site is different to the “chain” of activities required for a Cultural heritage site. Therefore, the EO services required to support Natural heritage sites are different to those required to support Cultural heritage sites. However, we have identified that there is some overlap, e.g. some few services can be used for both Natural and Cultural heritage sites.
An innovative technological emerging issue in the area of Cultural heritage is that the state-of-the-art enables the development of associated Digital Twins, this means the elaboration of a digital virtual representation of the Cultural heritage object (or site) that serves as the real-time digital counterpart of the physical Cultural Heritage object. A digital virtual tour of some heritage sites is starting to be available, further enhanced with virtual reality and virtual augmented reality. This is an area where there might be some overlap between the technologies required to implement ESA’s Digital Twin Earth concept, and the current technologies being used to develop digital twin cultural heritage objects.
The presentation will cover the current status for Natural heritage sites, this type of heritage is basically related to preserving selected Earth ecosystems. Since most of the EO satellites have been designed to monitor the Earth ecosystems, then, in the area of natural heritage sites, there are already some EO operational services being used for the benefit of Natural heritage. Major emphasis will then be done on the complexity related with Cultural heritage sites, the main problems identified, the current state-of-the art of research as well as some ideas to encourage discussion on what can be done to start working jointly towards the development of associated EO services for the benefit of Cultural heritage.
An eventual market for EO-based services to support Natural heritage and a potential market to support Cultural heritage might be in the process of building up. Some suggestions on how we could further encourage this momentum will be addressed.

Earth Observation and ground remote sensing non-contact technologies are considered innovative methods to support decision making and site management sustainable exploitation of cultural assets. The broad spectra of remote sensing techniques provide the ideal platform to undertake a wide range of practical, cost-efficient, and easily programmable studies, not easily acquired with other tools. In the case of cultural landscapes, these techniques offer the opportunity to ensure repeated monitoring of multiple parameters in a macro and micro spatial scale, offering European broad comparisons and contrasts.

Over the past few years, the advancement of satellite observations and space-based products and the availability of open-source software have revolutionised archaeological practices. As indicated by the relevant literature, Earth observation sensors have been widely adopted for archaeological purposes in the recent past [1-2]. In parallel, artificial intelligence image-based methods have also been populated in the relevant literature [3]. The contribution of the European Copernicus and other international space programs that provide free and full access to a range of datasets has been instrumental for the broader use of space-based observations for heritage monitoring [4-5]. Nevertheless, local stakeholders and policymakers call for concrete and tangible outcomes for their use [6].

This presentation summarises recent applications based on the European Copernicus space program and other international space programs for cultural heritage applications in Cyprus, developed through two collaborative research projects. The results presented here are part of NAVIGATOR [7] (Copernicus Earth Observation Big Data for Cultural Heritage, EXCELLENCE/0918/0052) and PERIsCOPE [8] (Portal for heritage buildings integration into the contemporary built environment, INTEGRATED/0918/0034).

Under the NAVIGATOR project, an overview of the Earth Observation contribution to cultural heritage disaster risk management is discussed. The overall risk cycle and the potential links between the space-based technologies for detection, monitoring and analysis of cultural heritage sites are presented [9]. In addition, the use of optical and radar Sentinel missions for detecting displacements within archaeological sites in Cyprus after a 5.6 magnitude scale earthquake event through big data cloud platforms such as the Hybrid Pluggable Processing Pipeline (HyP3) system are discussed (Fig. 1, [10]).

Change detection methods using optical images are presented, supporting thus needs for landscape studies and mapping the broader context of an area [11]. A case study for detecting fire intensity through optical Sentinel-2 images are also presented, implemented in a recent fire event in Cyprus (Aug. 2021). Under the PERIsCOPE project, the use of thermal Landsat-7 and -8 images for detecting hot-spot areas in the municipality of Limassol and Strovolos are discussed, supported by Google Earth big data cloud platform (Fig.2, [12]). In addition, the Google Earth platform was used to extract vegetation properties from Landsat 8 [13-14] and identified changes in vegetation cover over the two areas (Limassol and Strovolos) (Figure 3).


These examples are considered indicative concerning the broader aspects of how Copernicus and other space programs can support real needs of heritage protection and management. Their use and further elaboration can only benefit from integrating and adopting best practices by responsible stakeholders and policymakers.

Acknowledgements

The authors would like to acknowledge the NAVIGATOR project, co-funded by the Republic of Cyprus and the European Union's Structural Funds in Cyprus under the Research and Innovation Foundation grant agreement EXCELLENCE/0918/0052 (Copernicus Earth Observation Big Data for Cultural Heritage). Results related to the Landsat thermal analysis are part of the "Portal for heritage buildings integration into the contemporary built environment", in short PERISCOPE, co-financed by the European Regional Development Fund and the Republic of Cyprus through the Research & Innovation Foundation. Grant Agreement INTEGRATED/0918/0034. Lastly, the authors would like to acknowledge the project “Programma Operativo Nazionale Ricerca e Innovazione 2014-2020 - Fondo Sociale Europeo, Azione I.2 “Attrazione e Mobilità Internazionale dei Ricercatori” – Avviso D.D. n 407 del 27/02/2018” CUP: D94I18000220007 – cod. AIM1895471 – 2.

Figure Captions

Figure 1. (a) Unwrapped interferogram. (b) Vertical displacements. (c) Coherence map, enveloping important archaeological sites of Cyprus (Nea Paphos, Tombs of the Kings and the historic town centre) (source [10]).

Figure 2. Seasonal mean temperature over the Strovolos area (Cyprus), between the years 2013 and 2020. The red colour indicates higher mean temperatures, while the blue colour indicates lower mean temperatures.

Figure 3. NDBaI2 index estimated on Strovolos (Cyprus) (a) and Limassol (Cyprus) (b) over the period 2013 (on the left) - 2010 (on the right). NDBaI2 value is comprised between -1 (blue) and 1 (white).

References

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This paper presents an assessment of the use of the DESIS sensor, the imaging spectrometer mounted on the International Space Station (ISS), for the detection of burned areas in sensitive areas. Each DESIS acquisition records continuous spectral information over areas of 30 km × 30 km, a suitable size for such applications, in the visible and near infrared ranges across 235 spectral bands. As DESIS is the first hyperspectral sensor allowing rapid revisit of any site of interest excluding extreme high latitudes, pre- and post-event images can be available, where burned areas can be detected with change detection techniques coupled with suitable, narrow-band spectral indices. Such products may help in timely raising awareness on the endangerment of cultural and natural heritage sites and landscapes, emphasising the importance of Earth Observation (EO) data for monitoring, digitizing and documenting valuable cultural heritage sites.

A first assessment for the case of the Arakapas fire in Cyprus is presented. This event started on Saturday, the 3rd of July 2021 in the Limassol district near the village of Arakapas and was controlled after approximately 24 hours. The area affected by the fire is designated as an area of special aesthetic value of the Troodos mountain range to the South West Shores and is included in the Troodos UNESCO global geo-park, which characterizes it as a natural heritage landscape. According to the Department of Antiquities, there are 13 cultural heritage sites in the extended region of the fire. Indeed, several churches of significant cultural value were in danger, being located close to the fire. DESIS acquisitions in cloud-free conditions are available for the pre- and post-event dates of the 10th of June and 31st of July 2021, respectively. The difference of the narrow-band Normalized Differential Vegetation Index (NDVI), using the narrow bands centered around 620 and 700 nm respectively was used to identify the burned area. Results are favourably matched to available coordinates of known burned sites, and the affected area looks overall well identified according to the available information on the event. Short wave infrared (SWIR) information is usually characterized by relevant emissions in presence of fires and widely used for this kind of analysis. Nevertheless, results show that DESIS data yield precise burnt area maps, in spite of the lack of this spectral information.

Also 10 spectral bands of multispectral Sentinel-2 images from the 12th of June and 27th of July, with spatial resolution between 10 m and 20 m and a swath width of 290 km, were used to calculate different indices frequently applied for burned area assessment using EO data, such as the Normalised Burn Ratio (NBR), Burned Area Index (BAI), and dNBR (differential NBR) Results from these broadband indices are accurate, and are subsequently compared to the results of the narrowband outcomes from DESIS.

The standardization of scanning the Earth’s surface through multiple devices and sensors, coupled with the increasing availability of open access datasets and the development of algorithms for automatic analyses (especially for image recognition and classification), has allowed Landscape Archaeology to utilize such technologies for conducting valuable new studies. Nowadays, the evaluation of spatial and temporal patterns revealed via analyses of artefacts, sites, landscapes, and cultural phenomena is a fundamental step of every archaeological project. This approach facilitates comparisons and correlations between different types of information in relational databases and GIS, enriching the information derived from ground-level fieldwork and lab processing, improving the accuracy of the results and – most importantly – opening new lines of investigation.
The study presented here integrated archaeological and digital methodologies for the identification and classification of different archaeological features related to the long-term nomadic and semi-sedentary behavior of the hunter-gatherer and early pastoral groups occupying the Egyptian Western Desert (hereafter EWD) during the Early and Mid-Holocene.
In this period, the region played a key role as a zone of transition, transformation and exchange between the Sahara and the Nile Valley. These human groups living in the EWD experienced major environmental changes and repeated climatic oscillations that triggered transformations in their economy, mobility, and settlement patterns. Between the 7th and 6th millennia BC, the area of Wadi el Obeiyid in the Farafra Oasis witnessed the presence of semi-sedentary settlements, possibly related to a phase of increasing demographic pressure. The groups living in the area exploited the environment through a mixed economy based on hunting activities, gathering wild plants, ostrich exploitation, and caprine herding; they moved across long distances, especially for procurement of raw materials.
This study focused on two kinds of architectural features that should be related to these groups: slab structure sites, and a specific type of surface fireplace, named Steinplatz. The slab structures are features made of stone slabs vertically stuck in the silt layers and arranged in circular or oval shapes. They are believed to be foundations that originally supported perishable materials forming hut- or shelter-type structures. The Steinplatz hearths are burnt and fire-cracked stone-filled pits and are ubiquitous in the Sahara. They provide evidence of short-term encampments of people moving within the region and are an important archaeological marker of changes in patterns of the past human presence that this work aims to assess. Both slab-structures and Steinplatz have also been identified in other areas of the EWD (Dakhla, Kharga, Great Sand Sea, Gilf Kebir, Karkur Talh, and Jebel Uweinat).
Despite the efforts of several international research groups, due to the difficulty of ground-based surveys, especially after 2015, when access to the EWD was denied by the Egyptian Authorities due to security and safety concerns, identifying and assessing the distribution of these features is essentially impossible via traditional ground-based surveys. The application of a remote, automated, precise, and cost-effective method for feature detection will help us to overcome these obstacles and enrich the existing datasets.
The process applied in this project involved the application of appropriate (established) machine learning algorithms for image recognition (coded in Python/JavaScript) on multispectral and multitemporal satellite imagery, at very high and high resolution (0,6 to 10 m for optical imagery and 1 to 10 m for radar data), and different modalities of acquisition. The imagery derives from different sources (Hexagon KH-9, QuickBird-2, Sentinel 1 and 2, COSMO-SkyMed), and was assembled and processed through the Google Earth Engine Cloud Computing Geospatial Platform (hereafter GEE). The algorithms were coded to factor-in many relevant characteristics and archaeological proxy indicators (crop-, soil-, dump- and shadow-marks; archaeological and environmental hotspots; elevation and microtopography; surface roughness and discontinuity; weather conditions, electric conductivity and moisture content percentage of the soil). The training of the algorithms was performed on vectorized verified datasets of overlapped composite images (Multi-Temporal Aggregates) containing features already known in the archaeological record. The trained algorithms were then applied to an unverified satellite dataset of the same sources. The new results were collected, vectorized and checked within a relational database and a GIS through Error Rate with Cross-Entropy Validation.
The results of this study will provide essential information about human mobility patterns between the Eastern Sahara and the Nile Valley during the Holocene and will shed new light on the contribution of the Saharan communities in the emergence of the Egyptian civilization.

Archaeological and cultural heritage are precious and fragile assets that need to be preserved from degradation and, at the same time, need a proper valorization allowing people to easily access their historical, archaeological and material consistence. The methodological approach to the Cultural Heritage assets protection must therefore be multi-technology, multi-scale and multi sensor, in order to collect data from different data sources, whose correlation will allow a deeper comprehension of the phenomena in act and their best prevention.
Pomerium is a project under development proposed by an Italian consortium in the framework of ESA call “5G for l’ART” and aimed to demonstrate the applicability and effectiveness of a stack of multi-technology instruments and methodologies for the monitoring of the CH exposed to the multiple aggressions of the urban environment. The Area of Interest of the project is the historical center of Rome, with particular reference to Colosseum, Cestio Pyramide, Aurelian Walls and the urban path of Tiber.
Reference Users of the project, involved since the beginning in the planning and operational activities, are:
- Soprintendenza Speciale Archeologia, Belle Arti e Paesaggio of Rome (MIC);
- Parco Archeologico of Colosseum (MIC);
- Sovrintendenza Capitolina (Municipality of Rome).
The project articulates around four main use cases referred to the main risks that environmental and anthropic factors represent for CH:
- Ground or structure instability;
- Pollution;
- Waste and non-authorized soil use;
- Weed vegetation.
For each phenomena to keep under monitoring, a different set of technologies was combined in different configuration, in order to achieve a deep level of knowledge on the active phenomena and on the status of the exposed CH assets.
In detail, the scopes and methodologies of the different use cases are:
Ground or infrastructure instability:
Monitor the displacement phenomena affecting the interested CH assets and their environment, in order to identify and prevent damages and losses through the usage of the following instruments:
- DIFSAR interferometry from Cosmo SKY-Med data for the monitoring of displacements over time;
- On site-displacement sensors applied to a set of points identified by the remote analysis as most affected by displacement phenomena.
Pollution:
Monitor the distribution of urban pollutants around the CH assets and foresee the degradation effect on exposed surfaces through the use of:
- On site air quality sensors integrated by public networks data (ARPA and Municipality of Rome);
- Spray dispersion model, to simulate the distribution of pollutants around the interested surfaces;
- Regression model, to foresee the entity of regression phenomena on marble surfaces due to pollutant agents.
Waste, soil use:.
Detect illicit uses of the soil in protected environments, detect and monitor the presence of waste and debris. The monitoring activities interest the Tiber stretch in urban area (from Flaminio to Marconi) and count on:
- RPAS surveys with optical and IR camera and 360 camera;
- Interactive Virtual Reality environment for the representation of the monitoring results and as an operating environment in which the User may navigate the monitored areas in a realistic mode and identify features of his own interest.
Weed vegetation:
Detect and monitor the growth of weed vegetation on historical surfaces through the use of:
- RPAS surveys with optical and IR camera
- Interactive Virtual Reality environment.
The core of Pomerium is represented by the Web-GIS platform AWARE that will act as unique point of access for the Users to data and analysis produced in the different project’s scenarios. Users will be allowed to data consultation, data extraction and production of thematic reports useful to support their ordinary and extraordinary conservation tasks.

Climate change presents new challenges to ecosystems worldwide. Many ecosystems are currently in a state of transformation due to changing site factors, including the increase in annual mean temperature and the reduction in summer precipitation maxima combined with an increase in winter precipitation. These changes are particularly evident in the orchard meadow ecosystem. Orchard meadows provide habitats for numerous animals and plants which are considered extremely species-rich. Since they are extensively managed landscape elements, orchard meadows are not only affected by the prevailing site factors, they are also dependent on anthropogenic management and cultivation.
In southwestern Germany orchard meadows represent a precious cultural landscape element, where the domestic fruit tree stands are dominated by apple, pear, walnut and plum species. However, a dramatic decline in orchard tree populations was observed in the last decades, which can be attributed on the one hand to climate change effects and on the other hand to deficient management and cultivation. In this context, the primary objective of the project within this study will be to conserve orchard meadows and their multiple benefits in terms of ecosystem services. Furthermore, the objective will be to apply and adapt innovative approaches as well as to improve existing remote sensing techniques.
Forecasts indicate that climate change will increase the occurrence and severity of droughts and dry periods in Baden-Württemberg in the future. This fact confronts orchard meadow stands with numerous serious challenges. Already today, immense damage, which is regarded as the result of droughts, was documented at many sites. Droughts were one of the major causes for the mortality of orchard trees and for an increase in their sensitivity to illnesses and insect damage. Considering this challenge, the present study focuses on the detection, monitoring and evaluation of possible effects of the drought since 2016 on orchard stands and fruit trees. Thereby the study site covers an area of 11ha (about 1,100 trees) at the bottom of the Swabian Alb, which is representative for the local cultural landscape in regards of climatic and geomorphological conditions.
The first part of the approach detects single trees using nDSM and NDVI thresholding of the UAV data. The following part evaluates the development of the NDVI values for the identified tree pixels on the basis of Planet and Sentinel-2 data.
The underlying data are based on UAV flights with a 10-band multispectral camera. In the subsequent analysis of the data DSM and orthomosaics were generated by Structure-from-motion (SfM) techniques. Single trees in the high-resolution aerial images were detected through threshold method based on normalized digital surface models (nDSM) and the normalized difference vegetation index (NDVI). Objective of this process is to detect the tree crown footprints of the individual orchard trees. To analyze drought effects on orchard trees, the vegetation index NDVI will be calculated to estimate tree vitality based on Planet imagery time series as well as Sentinel-2 data. Planet imagery provides a suitable spatial (3 meter) and temporal resolution for crown detection of single orchard trees. Moreover, with regard to data consistency, data availability and radiometric quality the suitability of Sentinel-2 imagery will be tested and evaluated to estimate drought effects. In addition, a statistical evaluation in high-interval time series for each crown footprint was conducted over the study period (2016-2021).
It can be expected that the absent or lower water availability of the trees during the drought periods will be recognized as a deviation in the NDVI pixel trajectories of the single orchard trees. In combination with climate data from the surrounding German Weather Service (DWD) climate stations, the NDVI could serve as indicator for drought stress in orchard meadow stands.
This methodology intends to describe and evaluate the impact of drought on orchards and fruit production. Because these methods are transferable to other areas, the climatic effects on different conditions could be evaluated. Therefore, this method allows to determine future favourable but also unfavourable sites for fruit growing, especially for orchards meadows.