guidelines for enhancement of high...
TRANSCRIPT
GUIDELINES FOR ENHANCEMENT OF HIGH-RESOLUTION
LAYERS PRODUCED UNDER GMES INITIAL OPERATIONS (GIO) LAND MONITORING 2011 – 2013
Supplement to the documents:
GMES Initial Operations (GIO) Land Monitoring 2011 – 2013 in the framework of regulation (EU) No 911/2010 Pan-EU Component
Terms of Reference and template for national project plan
Framework service contract(s) for the provision of GMES Initial Operations 2011-2013 Land Monitoring Services: High Resolution
land cover characteristics of 5 main land cover types (6 lots). Ref-erence: Open call for tenders EEA/SES/11/004
Guidelines for verification of high resolution layers produced un-
der GMES Initial Operations (GIO) land monitoring 2011 - 2013
GMES Initial Operations (GIO) Land Monitoring 2011-2013
Guidelines for enhancement of high-resolution layers
21 May 2012 2
The Delegation Agreement is funded by the European Union in the context of the GMES programme
and implemented by European Environment Agency.
DISCLAIMER
The views expressed herein can in no way be taken to reflect the official opinion of the European Union.
Reporting information
Report title: Guidelines for enhancement of high-resolution layers
produced under GMES Initial Operations (GIO) Land
monitoring 2011 – 2013
Report number: N/A
Report website: N/A
Report version: 1.0
Date of preparation: 21.05.2012
Beneficiary organisation: National Land Cover Teams, Service Providers
Prepared by: György Büttner
Project coordinator: Hans Dufourmont
Project coordinator organisation: European Environment Agency
Project coordinator telephone number: +45 2494 1115
Project coordinator email address: [email protected]
GMES Initial Operations (GIO) Land Monitoring 2011-2013
Guidelines for enhancement of high-resolution layers
21 May 2012 3
1 Contents
2 Executive summary ......................................................................................................................... 4
3 Background and purpose of the document ..................................................................................... 5
4 Purpose of the enhancement .......................................................................................................... 5
5 Basic principles of enhancement .................................................................................................... 7
6 Strategies of enhancement ............................................................................................................. 9
6.1 ENHANCEMENT BASED ON GENERAL OVERVIEW ........................................................................... 9 6.2 ENHANCEMENT BASED ON LOOK-AND-FEEL VERIFICATION ............................................................ 9 6.3 DECISION BASED ON QUANTITATIVE VERIFICATION ....................................................................... 9
7 Data specification .......................................................................................................................... 10
8 Examples ....................................................................................................................................... 20
8.1 HRL IMPERVIOUSNESS ............................................................................................................ 20 8.2 HRL TREE COVER DENSITY ...................................................................................................... 20 8.3 HRL FOREST TYPE MAP ........................................................................................................... 20 8.4 HRL GRASSLAND MAP ............................................................................................................. 23 8.5 HRL WETLAND MAP ................................................................................................................ 23 8.6 HRL MAP OF PERMANENT WATER BODIES ................................................................................. 23
9 Annex 1: HRL Enhancement report template ............................................................................... 24
Acknowledgements ............................................................................................................................... 25
GMES Initial Operations (GIO) Land Monitoring 2011-2013
Guidelines for enhancement of high-resolution layers
21 May 2012 4
Revision history
Revision nr. Date Modified by Comments
2 Executive summary
Five1 high-resolution layers (HRL) will be produced in the frame of GIO Land (2011-2013)
covering EEA39: imperviousness, forests (tree cover density and forest type), grasslands,
wetlands and permanent water bodies. Service Providers are in charge of production of the
HRLs. The so-called intermediate products (20 x 20 m resolution) will be verified by national
teams (if national teams are not interested, by Service Providers).
Additionally, enhancement of the products is to be done in order to improve the intermediate
HRLs based on the results of the verification. Enhancement shall be carried out on the in-
termediate products at full resolution (20m x 20m, in national projection), based on existing
reference data (e.g. ground survey, topographic maps, thematic maps, aerial photography or
others). Similarly to verification, enhancement is done by national teams (if national teams
are not interested, by Service Providers).
Countries (and Service Providers) are expected to use the available resources (expertise,
budget and the best in-situ data) in an optimal way to increase the accuracy of the interme-
diate product to the feasible maximum. The enhancement should consist of reduction of
commission and omission errors. Commission errors (to be deleted from the intermediate
database) can be handled in case of all HRLs. However, omission errors) can be dealt with
only in case of map layers and not with density layers. The results of the enhancement will
be coded with different attributes than those used by SPs in the intermediate dataset. Con-
trary to the verification procedure, where former Eionet experience exists, no such previous
experience is available for the enhancement.
The purpose of this document is to provide guidelines for the enhancement to be applied for
HRLs produced under GIO-land. This document should be considered as a „living document‟
and will be shaped as experience will accumulate.
1 In reality there are 6 layers, because of two layers in forestry
GMES Initial Operations (GIO) Land Monitoring 2011-2013
Guidelines for enhancement of high-resolution layers
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3 Background and purpose of the document
The Land monitoring service of the Global Monitoring of Environment and Security
(GMES) led by DG ENTR2 of the European Commission, has entered its Initial Operations
(GIO) phase following the entry into application of Regulation (EU) n°911/2010 of 22 Sep-
tember 2010 of the European Parliament and the Council on the European Earth monitoring
programme (GMES) and its initial operations (2011 to 2013).
Pursuant to the GMES Work Programme 2011 these activities will start with the production
of the 5 High Resolution pan-European layers. To that aim, a call for tender has been or-
ganised, comprising 6 lots, following a distribution according to a combination of geographic
and thematic criteria. On 5th October 2011 the EEA addressed the National Focal Points and
National Reference Centres Land Cover in 39 European countries requesting for a letter of
intent for participation in GIO Land. The request was accompanied with a Terms of Refer-
ence and template for national project plan.
Some of the tasks in the Technical Specification, namely “Verification of high-resolution lay-
ers (HRL)” and “Enhancement of HRLs” were not fully described in technical terms and
“comprehensive guidelines” were promised to the countries as well as to Service Providers
(SP) in a later stage. Guidelines for verification are presented in a separate document3, re-
ferred to as GLV in this document. The purpose of the present document is to provide guide-
lines for enhancement of high-resolution layers. Contrary to the verification, where former
Eionet experience exists (Fast Track Service Land Monitoring), no such experience is avail-
able for the enhancement.
4 Purpose of the enhancement
The envisaged purpose of the enhancement is to improve the quality of the intermediate
HRL products (20m x 20m) produced by SPs. Following the enhancement, the intermediate
product will become the final product. In a majority of countries verification and enhancement
is foreseen to be done by the national teams. However, in some countries enhancement will
be done by the SP, if the country is not interested in participating in this process. Responses
of countries regarding intention of participation in verification and enhancement are included
in Table 1. (Note that response is pending for some countries.)
Enhancement means:
Removing an area from the intermediate HRL produced by the SP, because there is
evidence showing that the area does not belong to the HRL (i.e. commission error).
Supplementing the intermediate HRL produced by the SP with an area, because
there is evidence showing that the area does belong to the HRL (i.e. omission error).
2 Directorate General Enterprise and Industry
3 Guidelines for verification of High-Resolution Layers Produced under GMES Initial Operations (GIO) Land Monitoring 2011 –
2013, EEA, April 2012 (Version 2)
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Guidelines for enhancement of high-resolution layers
21 May 2012 6
Table 1 Interest of countries in verification and enhancement (status: 15 May 2012)
country Interested in verification Interested in enhancement
Albania + +
Austria + +
Belgium + +
Bosnia and Herzegovina + +
Bulgaria + + Croatia + +
Cyprus + +
Czech Republic + +
Denmark + +
Estonia - -
Finland + +
France + +
Germany + *
Greece + +
Hungary + +
Iceland + +
Ireland + -
Italy + +
Kosovo - -
Latvia + -
Liechtenstein + +
Lithuania + +
Luxemburg - -
FYR of Macedonia + -
Malta + +
Montenegro + +
The Netherlands + +
Norway + - Poland * *
Portugal + *
Romania + +
Serbia + +
Slovak Republic + +
Slovenia + -
Spain + +
Sweden - - Switzerland * *
Turkey + + United Kingdom + + Interested: at least 34 at least 26
* response is pending
GMES Initial Operations (GIO) Land Monitoring 2011-2013
Guidelines for enhancement of high-resolution layers
21 May 2012 7
The following six intermediate products (20m x 20m, national projection) will be subject to
enhancement:
Imperviousness density (or built-up map)
Tree cover density (or tree cover map)
Forest type map
Grasslands map
Wetlands map
Map of permanent water bodies
5 Basic principles of enhancement
Determining density values (imperviousness and tree cover) needs a dedicated processing
methodology4, which is rarely available at country level. Consequently, errors of omission
found in the imperviousness and tree cover density datasets are not expected to be correct-
ed by the countries with regards to the density values itself, only by the SPs (in cases where
the country is not interested in implementing enhancement). Countries will only be able to
enhance the built-up map (produced from imperviousness by applying a threshold to the
density values) and the tree cover map (produced from tree cover densities by applying a
threshold), respectively (see Ch. 6.2 in GLV). However, outlines of missing patches (i.e.
omitted in intermediate HRL) for impervious areas and tree-covered areas should be provid-
ed where possible, but not the density values inside the outlined patches (Table 2). These
patches can then be used in the next inventory of the HRL density product (i.e. in the opera-
tional phase of GMES) by the SP who will produce the updated HRL density product.
Table 2 Possibilities to correct omission errors (adding new areas to the HRLs) by en-
hancement
HRL Density / Map Enhancement by
countries Enhancement by
SP
Imperviousness Density not possible possible
Built-up map (derived by using 30% threshold)
possible5 NA
Tree cover
Density not possible possible
Tree-cover map (derived by using 30% threshold)
possible6 NA
Forest type Map possible possible
Grassland Map possible possible
Wetland Map possible possible
Permanent water Map possible possible
4 Processing of calibrated HR satellite imagery
5 Outlines of omitted impervious areas should be provided but not densities
6 Outlines of omitted areas with tree cover should be provided but not densities
GMES Initial Operations (GIO) Land Monitoring 2011-2013
Guidelines for enhancement of high-resolution layers
21 May 2012 8
Removing areas (commission errors) from HRL is possible from density layers, as well as
from map layers.
It is not easy to provide general guidance for the enhancement which is valid for all six HRLs
to be enhanced. However, the following basic principles are important to consider:
The volume of the enhancement, i.e. the work to be done depends on: (1) quality of
the SP‟s intermediate product; (2) quality of in-situ data; (3) available technical tools;
(4) available manpower and expertise and (5) budget. Usually it will be not realistic
aim to enhance the product to have 100% accuracy, but to use the available re-
sources in an optimal way to increase the accuracy of the intermediate product to the
feasible maximum.
An enhancement over the whole area of a country (even if less complete) is preferred to a very intense focus on a specific region (and then no resources to cover the rest of the country).
The enhancement should be based on the best available in-situ data. Potential in-situ
data for each HRL are listed in GLV Ch. 8. “Best” is meant regarding completeness,
timeliness, resolution, etc.
If an existing thematic map (database) is used as in situ source, control by recent or-
tho-photo is highly recommended to avoid the transfer of inconsistencies of the map
(database) into the HRL.
The enhancement should consist of a reduction of commission and omission errors,
as pointed out in Ch.4. The results of the enhancement should be coded with differ-
ent attributes than those used by SPs in the intermediate datasets, in order to clearly
separate the intermediate product and the enhanced one.
No preference is given to automated or manual enhancement methods. The selected
method should depend on the type of in-situ data and availability of technical tools.
Even if an automated process is used, some human control is indispensable to avoid
degradation of the HRL quality by errors of the in-situ data. In addition to the usual
problem of thematic maps, i.e. being frequently outdated, pre-dating of databases al-
so can occur, i.e. showing a status planned in the future.
If a good quality, recent built-up database is available there seems to be an easy way to en-
hance the imperviousness layer; not only the built-up map, but also the densities by placing the
20m x 20m grid on top of the built-up map, calculating the densities and having them substituted
into the intermediate layer.
This solution is not recommended, because:
There is a scaling difference between the densities derived by SPs, extracted from satel-
lite imagery, and densities based on in-situ data. I.e. the densities provided by the pre-
liminary data processing will not necessarily be compatible with densities produced by
the enhancement. This might introduce mistakes in the final 100m x 100m products by
SP.
GMES Initial Operations (GIO) Land Monitoring 2011-2013
Guidelines for enhancement of high-resolution layers
21 May 2012 9
6 Strategies of enhancement
The basis of the enhancement process should be the result of the verification. As shown in
GLV the following types of verification processes are carried out:
General overview of data quality (mandatory, qualitative)
Look and feel (mandatory, qualitative)
Statistical verification (highly recommended, quantitative)
6.1 Enhancement based on general overview
If no significant systematic mistakes are identified during verification, the result of general overview can be used to guide the enhancement. Based on an ordered list of disagreements between the HRL and the best available in-situ data, disagreements with the largest area can be examined. If the disagreement is confirmed to be an error of the HRL product, it can be corrected.
Benefits: largest decrease in misclassified area (omission and commission errors) can be achieved.
Drawbacks: if the best available in-situ data are not up-to-date, there will be lots of false-alarms, i.e. disagreements that are not mistakes of the HRL, but mistakes of the in-situ data. For this reason use of up-to-date ortho-photos for control is highly recommended.
6.2 Enhancement based on look-and-feel verification
If look-and-feel verification shows that one or more strata of the HRL are not precise enough, but the product is otherwise good, the efforts of enhancement can concentrate on these problematic strata.
Benefits: enhancement proceeds stratum-wise, which is easy for the operator. E.g. in HRL Imperviousness settlements or continuity of highways are checked.
Drawbacks: non-systematic mistakes with large area might not be corrected.
6.3 Decision based on quantitative verification
If statistical analysis shows that the accuracy of the intermediate HRL is below 80% and de-pending on the amount of effort needed to achieve the requested 85% accuracy7, the 3 stakeholders involved (EEA, country and SP) shall meet (teleconference) to analyse the sit-uation and to discuss appropriate mitigation measures, working closely together in order to reach a good final result.
7 The required man days have to be estimated.
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7 Data specification
Table 3 List of products as results of the enhancement
HRL Product name Product
no.
Imperviousness
Enhanced HRL Imperviousness, 20m x 20m,
national projection, enhanced by SP 1a
Enhanced HRL Imperviousness, 20m x 20m,
national projection, enhanced by country 1b
Forests
Tree cover
density
Enhanced HRL Tree cover density, 20m x
20m, national projection, enhanced by SP 2.1a
Enhanced HRL Tree cover density, 20m x
20m, national projection, enhanced by country 2.1b
Forest type Enhanced HRL Forest Type, 20m x 20m, na-
tional projection, enhanced by country or SP 2.2
Grasslands Enhanced HRL Grassland, 20m x 20m, na-
tional projection, enhanced by country or SP 3
Wetland Enhanced HRL Wetland, 20m x 20m, national
projection, enhanced by country or SP 4
Permanent
water bodies
Enhanced HRL Permanent water bodies, 20m
x 20m, national projection, enhanced by coun-
try or SP
5
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21 May 2012 11
Product 1a: Detailed specification of the Enhanced HRL Imperviousness (enhanced by SP)
Product
Enhanced Degree of Imperviousness 2012, 20m x 20m, national projection
Methodology
Based on the results of verification the Service Provider enhanced the intermediate De-gree of Imperviousness product.
Geometric resolution
Pixel size 20m x 20m
Coordinate Reference System
National projection systems for country data sets
Geometric accuracy (positioning scale)
According to ortho-rectified satellite imagery delivered by ESA (target accuracy: 20m RMSE)
Verification
Not planned
Data type
Raster
Raster coding
Thematic pixel values 0: all non-impervious areas in intermediate product 1-100: imperviousness values in intermediate product 101-200: imperviousness values obtained during enhancement (correcting omission errors) 201: all non-impervious areas obtained during enhancement (correcting commission errors) 254: unclassifiable (no satellite image available, or clouds, shadows, or snow)
255: outside area
Metadata
According to INSPIRE metadata standards
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Guidelines for enhancement of high-resolution layers
21 May 2012 12
Product 1b: Detailed specification of the Enhanced HRL Imperviousness (enhanced by
country)
Product
Enhanced Degree of Imperviousness 2012, 20m x 20m, national projection
Methodology
Based on the results of verification, the country enhanced the intermediate Degree of Im-perviousness product. Adding new densities into the database (reducing omission errors) is not possible. Instead, the Built-up map derived from HRL Imperviousness (by using a 30% threshold) has been enhanced. Patches of erroneous Built-up areas (commission errors) have been marked in the intermediate Degree of Imperviousness database.
Geometric resolution
Pixel size 20m x 20m
Coordinate Reference System
National projection systems for country data sets
Geometric accuracy (positioning scale)
According to ortho-rectified satellite imagery delivered by ESA (target accuracy: 20m RMSE)
Verification
Not planned
Data type
Raster
Raster coding
Thematic pixel values 0: all non-impervious areas in intermediate product 1-100: imperviousness values in intermediate product 101: all built-up areas obtained during the enhancement process (correcting omission errors) 102: all non-built-up (non-sealed) areas obtained during the enhancement process (correcting commission errors) 254: unclassifiable (no satellite image available, or clouds, shadows, or snow)
255: outside area
Metadata
According to INSPIRE metadata standards
GMES Initial Operations (GIO) Land Monitoring 2011-2013
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21 May 2012 13
Product 2.1a: Detailed specifications for the Enhanced HRL Tree cover density (enhanced
by SP)
Product
Enhanced tree cover density 2012, 20m x 20m, national projection
Methodology
Based on the results of verification the Service Provider enhanced the intermediate Tree
Cover density product.
Geometric resolution
Pixel resolution 20m x 20m
Coordinate Reference System
National projection systems for country data sets
Geometric accuracy (positioning scale)
According to ortho-rectified satellite imagery delivered by ESA
Verification
Not planned
Data type
Raster
Raster coding
Thematic pixel values 0: all non-tree areas in intermediate product 1-100: tree cover densities in intermediate product 101-200: tree cover densities obtained during enhancement process (correcting omission errors) 201: all non-tree cover areas obtained during enhancement process (correcting commission errors) 254: unclassifiable (no satellite image available, or clouds, shadows, or snow) 255: outside areas
Metadata
According to INSPIRE metadata standards
GMES Initial Operations (GIO) Land Monitoring 2011-2013
Guidelines for enhancement of high-resolution layers
21 May 2012 14
Product 2.1b: Detailed specifications for the Enhanced HRL Tree cover density (enhanced
by country)
Product
Enhanced tree cover map 2012, 20m x 20m, national projection
Methodology
Based on the results of verification the country enhanced the intermediate Tree cover
density product. Adding new densities into the database is not possible (reducing omis-
sion errors). Instead, the Tree cover map derived from HRL Tree Cover density (by using
a 30% threshold) has been enhanced. Patches of erroneous Tree-cover areas (commis-
sion errors) have been marked in the intermediate Tree cover density database.
Geometric resolution
Pixel resolution 20m x 20m
Coordinate Reference System
National projection systems for country data sets
Geometric accuracy (positioning scale)
According to ortho-rectified satellite imagery delivered by ESA
Verification
Not planned
Data type
Raster
Raster coding
Thematic pixel values 0: all non-tree areas in intermediate product 1-100: tree cover densities in intermediate product 101: all tree areas obtained during the enhancement process (correcting omission errors) 102: all non-tree areas obtained during the enhancement process (correcting commission errors) 254: unclassifiable (no satellite image available, or clouds, shadows, or snow) 255: outside area
Metadata
According to INSPIRE metadata standards
GMES Initial Operations (GIO) Land Monitoring 2011-2013
Guidelines for enhancement of high-resolution layers
21 May 2012 15
Product 2.2: Detailed specifications for Enhanced HRL Forest type
Product
Enhanced HR Forest type 2012, 20m x 20m, national projection
Methodology
Based on the results of verification the intermediate HRL Forest Type map has been en-
hanced by country or by Service Provider. In addition to the dominant leaf type layer (de-
ciduous, coniferous) the support grid (including “trees used for agricultural practices” and
“trees in urban context”) might have been also enhanced. Patches of erroneous areas
(omission and commission errors) have been integrated into the intermediate database.
Geometric resolution
Pixel resolution 20m x 20m, 0.5 ha MMU
Coordinate Reference System
National projection systems for country data sets
Geometric accuracy (positioning scale)
According to ortho-rectified satellite imagery delivered by ESA
Verification
Not planned
Data type
Raster
Raster coding
Thematic pixel values for dominant leaf type grid 0: all non-tree areas in intermediate product 1: broadleaf forest in intermediate product 2: coniferous forest in intermediate product 101: all broadleaf forest obtained during the enhancement process (correcting omission errors) 102: all coniferous forest obtained during the enhancement process (correcting omission errors) 105: all non-tree areas obtained during the enhancement process (correcting commission errors) 254: unclassifiable (no satellite image available, or clouds, shadows, or snow) 255: outside area
Thematic pixel values for additional support grid on non-forest trees 0: all non-tree areas in intermediate product 3: trees predominantly used for agricultural practices in intermediate product 4: trees in urban context, in intermediate product 103: trees predominantly used for agricultural practices obtained during the enhancement process (correcting omission errors) 104: trees in urban context, obtained during the enhancement process (correcting omission errors) 254: unclassifiable (no satellite image available, or clouds, shadows, or snow) 255: outside area
Metadata
According to INSPIRE metadata standards
GMES Initial Operations (GIO) Land Monitoring 2011-2013
Guidelines for enhancement of high-resolution layers
21 May 2012 16
This layer (product 2.2) includes two grids (GLV, Table 2b): (1) a dominant leaf type grid
(deciduous and coniferous) and (2) additional support grid with non-forest data (trees used
for agricultural purposes and trees in urban context). The HRL Forest type is produced by
GIS operation using these two layers. Therefore enhancement should tackle both grids (Ta-
ble 4).
Table 4 Enhancement of HRL Forest type (cases simplified)
HRL Forest type
intermediate product
In-situ data Action
Forest non-
forest
case 1:
non-forest trees (agriculture or
urban use)
Enhance the support
grid (reduce omission
error in support grid, i.e.
commission error in
forest type grid)
case 2:
non-trees
Enhance the dominant
leaf type grid (reduce
commission error)
Non-forest forest Enhance the dominant
leaf type grid (reduce
omission error)
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Product 3: Detailed specification for Enhanced HRL Grassland
Product
Enhanced HRL Map of permanent grassland 2006-2009-2012, 20m x 20m
Methodology
Based on the results of verification the intermediate HRL Grassland map has been en-hanced by country or by Service Provider. Patches of erroneous areas (omission and commission errors) have been integrated into the intermediate database.
Geometric resolution
Pixel resolution 20m x 20m
Coordinate Reference System
National projection systems for country data sets
Geometric accuracy (positioning scale)
According to ortho-rectified satellite imagery delivered by ESA (target accuracy: 20m RMSE)
Verification
Not planned
Data type
Raster
Raster coding
Thematic pixel values 0: all non-grassland areas in intermediate product 1: grassland areas in intermediate product 101: all grassland areas obtained during the enhancement process (correcting omission errors) 102: all non-grassland areas obtained during enhancement process (correcting commission errors) 254: unclassifiable (no satellite image available, or clouds, shadows, or snow) 255: outside area
Metadata
According to INSPIRE metadata standards
GMES Initial Operations (GIO) Land Monitoring 2011-2013
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21 May 2012 18
Product 4: Detailed specification for Enhanced HRL Wetland
Product
Enhanced HRL Wetland map 2012, 20m x 20m
Methodology
Based on the results of verification the intermediate HRL Wetland map has been en-hanced by country or by Service Provider. Patches of erroneous areas (omission and commission errors) have been integrated into the intermediate database.
Geometric resolution
Pixel resolution 20m x 20m
Coordinate Reference System
National projection systems for country data sets
Geometric accuracy (positioning scale)
According to ortho-rectified satellite imagery delivered by ESA (target accuracy: 20m RMSE)
Verification
Not planned
Data type
Raster
Raster coding
Thematic pixel values 0: all non-wetland areas in intermediate product 1: wetland areas in intermediate product 101: all wetland areas obtained during the enhancement process (correcting omission errors) 102: all non-wetland areas obtained during enhancement process (correcting commission errors) 254: unclassifiable (no satellite image available, or clouds, shadows, or snow) 255: outside area
Metadata
According to INSPIRE metadata standards
GMES Initial Operations (GIO) Land Monitoring 2011-2013
Guidelines for enhancement of high-resolution layers
21 May 2012 19
Product 5: Detailed specification for Enhanced HRL Permanent water bodies
Product
Enhanced HRL Permanent water bodies 2006-2009-2012, 20m x 20m
Methodology
Based on the results of verification the intermediate HRL Permanent water bodies map
has been enhanced by country or by Service Provider. Patches of erroneous areas (omis-
sion and commission errors) have been integrated into the intermediate database.
Geometric resolution
Pixel resolution 20m x 20m
Coordinate Reference System
National projection systems for country data sets
Geometric accuracy (positioning scale)
According to ortho-rectified satellite imagery delivered by ESA (target accuracy: 20m RMSE)
Verification
Not planned
Data type
Raster
Raster coding
Thematic pixel values 0: all non-permanent water areas in intermediate product 1: all permanent water areas in intermediate product 101: all permanent water areas obtained during the enhancement (correcting omission errors) 102: all non- permanent water areas obtained during enhancement (correcting commission errors) 254: unclassifiable (no satellite image available, or clouds, shadows, or snow) 255: outside area
Metadata
According to INSPIRE metadata standards
GMES Initial Operations (GIO) Land Monitoring 2011-2013
Guidelines for enhancement of high-resolution layers
21 May 2012 20
8 Examples
Contrary to the verification, where former Eionet experience exists (Fast Track Service Land
Monitoring), no such experience is available for the enhancement. At the moment very few
real examples are available, therefore hypothetic examples are provided. The number of real
examples will grow during the training workshops and the implementation of the project.
8.1 HRL Imperviousness
Fringe zones of built-up areas, characterised with moderate imperviousness densities are sometimes omitted from HRL Imperviousness (see Example 1 from GLV).
In situ data used: topographic map and recent colour ortho-photo
Layer to be enhanced: Built-up map (because densities, compatible with the ones provided by the SP are not possible to derive; see Ch.5)
Enhancement based on: “look-and-feel” of rural settlements
Way of enhancement: visual delineation of the outline of the missing area, based on the ortho-photo as spatial reference. The HRL Built-up map was displayed to achieve precise delineation.
The HRL Imperviousness (density) data have to be checked also in order to see if the area was missing because of the 30% threshold applied in deriving the HRL Built-up map.
8.2 HRL Tree cover density
The country enhances the tree cover map derived from HRL Tree cover density by applying
a 30% threshold.
Example: Fields planted with energy crop8 is removed from tree cover density map
(commission error).
8.3 HRL Forest type map
Example 2 from GLV is used for the demonstation.
In situ data used: topographic map and recent colour ortho-photo. Topographic map is outdated (see missing forest patch at the yellow arrow).
Layer to be enhanced: HRL Forest type map
Enhancement based on: “look-and-feel” of wet forests
Enhancement (removal of commission errors): the area with commission error (blue arrow) is outlined on the ortho-photo, coded by 105 (Product 2.2) and added to the intermediate product.
Enhancement (removal of omission errors): The area with omission error (yellow ar-row) is outlined on the ortho-photo, coded by 101 (Product 2.2) and added to the in-termediate product.
No modification in the additional support grid was needed (neither trees with agricul-ture nor with urban use are present).
8 The classifier was confused by the spectral signature of the energy crop (similar to broadleaved forest)
GMES Initial Operations (GIO) Land Monitoring 2011-2013
Guidelines for enhancement of high-resolution layers
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Example 1: Omission error in HRL Imperviousness (2006) Top: Topographic map with HR built-up area map (pro-duced with 30% threshold on Soil Sealing Enhancement 2006 data) overlaid (black/yellow outlines) Middle: IMAGE2006 Bottom: VHR natural colour orthophoto Location: Mihályi, Hungary Enhancement: SW part of the built-up area is outlined on the ortho-photo, coded by 101 (Product 1b) and added to the intermediate product. Densi-ties cannot be estimated by countries, only by SPs.
GMES Initial Operations (GIO) Land Monitoring 2011-2013
Guidelines for enhancement of high-resolution layers
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Example 2: Commission and omission errors in HRL Forest (2008) Top: Topographic map with HR Forest area overlaid (red outlines) Bottom: VHR natural colour orthophoto Middle: IMAGE2006 (addition-al data) Location: Near Zalakaros, Hungary Enhancement:
The area with commission error (blue arrow) is out-lined on the ortho-photo, coded by 105 (Product 2.2) and added to the interme-diate product.
The area with omission error (yellow arrow) is out-lined on the ortho-photo, coded by 101 (Product 2.2) and added to the interme-diate product.
No modification in the ad-ditional support grid was needed (neither trees with agriculture nor with urban use are present).
GMES Initial Operations (GIO) Land Monitoring 2011-2013
Guidelines for enhancement of high-resolution layers
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8.4 HRL Grassland map
Example: a hayfield indicated by a recent ortho-photo is included in the intermediate HRL
grassland map product (omission error). Enhancement based on delination of the missing
grassland area on the orthophoto. Code = 101 (product 3).
8.5 HRL Wetland map
Example: a wetland indicated by the national wetland map and confirmed by a recent
orthophoto is not included in the the intermediate HRL wetland map. Enhancement based on
delination of the missing wetland area on the orthophoto or taking over the outline from the
national wetland map, if it is precise enough. Code = 101 (product 4).
8.6 HRL Map of permanent water bodies
A liquid dumpsite shown by the national topographic map is erronously included in the inter-
mediate map of HRL water bodies. Enhancement based on excluding the water body from
the intermediate HRL water map based on information of the topographic map. Code = 102
(product 5).
GMES Initial Operations (GIO) Land Monitoring 2011-2013
Guidelines for enhancement of high-resolution layers
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9 Annex 1: HRL Enhancement report template
The report shall be identical for all HRLs.
I. Administrative part
High Resolution Layer
Country (and region, if regions are analyzed separately)
Institution carrying out the work
Expert carrying out the work (name, position and e-mail)
Internal quality control by (name, position and e-mail)
Date and place of writing the report
II. Technical part
Which methods of the verifica-tion were used to guide the en-hancement? (write (X) in the appropriate box)
( ) General overview of data quality ( ) Look-and-feel analysis ( ) Statistical verification
In situ data used. Replace Data-1 with the proper type. How can you estimate the usa-bility / quality of in-situ data (ex-cellent, good, average, bad, very bad – keep one answer only)
Data-1 (excellent, good, average, bad, very bad)
Data-2 (excellent, good, average, bad, very bad)
….
Data-n (excellent, good, average, bad, very bad)
Methodology of enhancement (write (X) in the appropriate box)
( ) Fully automatic ( ) Semi-automatic with lots of manual editing ( ) Semi-automatic with few manual editing ( ) Fully manual
Removal of commission errors: Which kind of improvement has been achieved?
(Provide short text about the types and quantity of mis-takes removed)
Removal of omission errors: Which kind of improvement has been achieved?
Provide short text about the types and quantity of mis-takes removed)
Provide an overall evaluation of the improvements achieved: (excellent, good, average, mod-est, weak– keep one answer only)
excellent means that most of the errors were eliminated good means that at least 75% of errors were eliminated average means that around 50% of errors were eliminat-ed modest means that about 25% of errors were eliminated weak means that less than 25% of errors were eliminated