EAGL Eionet working group on data model for land monitoring

Transcription

1 Minutes Prjects Activity Participants EAGL Einet wrking grup n data mdel fr land mnitring 3 rd wrking meeting Gergely Maucha, Geir-Harald Strand, Gerard Hazeu, Guillerm Villa, Philippe Dreln, Tmas Sukup, Geff Smith, Stefan Kleeschulte, Michael Bck, Stephan Arnld, Gebhard Bank, Gerge Buttner, Vasc Nunes, Andreas Littkpf, Antni Nunes, Ales Versic, Núria Blanes Date 10-12/03/2010 Prepared by: Cmments: Núria Blanes, Geff Smith, Andreas Littkpf, Gebhard Bank Geir-Harald Strand, Gerard Hazeu, Philippe Dreln, Gerge Buttner, Stefan Kleeschulte, Tmas Sukup, Vasc Nunes, Guillerm Villa, Geff Smith 1. INTRODUCTION AND OBJECTIVES OF THE MEETING This meeting intends t cntinue the wrk already started in 2009 by the Einet wrking grup n data mdels fr land mnitring. This meeting is the first ne that is cnsidered as a NRC meeting and therefre, financial and administrative supprt have been prvided by EEA. The main bjectives f the meeting were: (1) t establish the basic classes t be mapped and the attributes defining each f thse classes based n experiences presented by the grup and previus knw hw, in rder t pave the way n hw land mnitring in Eurpe can evlve frm the existing CORINE t a technically mre advanced methd t prduce harmnised land cver and land use infrmatin at Eurpean level frm existing surces (e.g. natinal inventries), and (2) t discuss n GIO. The wrkshp has been divided int a general sessin f presentatins cncerning the wrk dne by several members f the grup, splinter sessins t discuss parameterizatin and attributes t the different elements and finally, a sessin t develp recmmendatins fr GIO and based n EEA s request fr the next CLC in The last day was dedicated t summarize the utcmes f the splinter sessins, t draw sme cnclusins n hw t prceed and decide which will be the wrk t be dne by each partner in the cming mnths. 2. GENERAL PRESENTATIONS OF THE WORK COMMITTED TO BE DEVELOPED IN THE LAST THREE MONTHS In this sessin, there were 3 presentatins. FAO representative was nt able t participate, s the sessin directly started with (1) the translatin prcess f the CLC 3 rd level class int FAO nmenclature, (2) the translatin f existing CLC int bject riented data mdels, based n SIOSE develpments, and (3) gaps already identified in the exercise f CLC 2006 and imprvements prpsed fr the future. Technical details n the findings presented in the afternn sessin can be fund as an Annex t these minutes (infrmatin prvided by the speakers). MnF_EAGLE3rdmeeting_Lisbn_March10_ /10

2 Eurpean Tpic Centre Land Use and Spatial Infrmatin Due t time cnstraints, valuable wrk develped by ther members f the grup has nt been presented during this meeting, but the infrmatin wuld be prvided in the next EAGL meeting r via a cmmn publicatin. 2.1 Translatin prcess f the CLC 3 rd level class int FAO nmenclature (Vasc Nunes) The bjective f the wrk dne is the translatin f CLC nmenclature int FAO Meta language in rder t test hw Crine can be described using FAO tls and nmenclature. Several items shuld be taken int accunt fr this translatin, and nt all f them can be slved with FAO mdel (different degrees f translatin depending n the CLC class and it varies frm successful translatin t a questinable and very questinable ne). Mixed / hetergeneus classes (e.g. 242, 243, 244, 324, etc) were especially difficult t translate.. It has been discussed the aim f this exercise and the fields in which this wrk can be used. It has been agreed that it can explain in a mre detailed way the cntent f the CLC classes and t really check the cmparability amng the different natinal teams. Based n these types f studies, the variatins and differences acrss Eurpe regarding the definitin f the land cver classes need t be btained. What is really imprtant fr the parameterizatin exercise is that it aims t btain a single definitin at Eurpean level. 2.2 Translatin f existing CLC int bject riented data mdels, based n SIOSE develpments (Guillerm Villa) When ding the exercise, it has been seen that sme CLC subclasses already in place shuld disappear and the infrmatin shuld be integrated int the crrespnding class as an attribute (e.g. abandnment, under cnstructin, types f frest, ), and infrmatin that shuld be prvided as a percentage instead f a new class detailing the degree f cverage, fr example. At natinal level, each user can decide which elements are parts f a land cver r nt, but at Eurpean level it shuld be agreed in rder t ensure harmnisatin and cmparability. Several questins arse frm the presentatin and were discussed, such as a) hw tw plygns then can be split if yu nly have different attributes but the same general label, r b) the relatin f this exercise with the MMU (if yu strictly apply MMU, then it seems that there is n difference between attributes r classes), r c) if Crine plygns culd be described nly using statistical data that will be available at Eurpean level by grid cells f 100*100m. Depending n the purpse f the analysis, there are (at least) 2 ptins at the CLC plygn level (explained by Nrway): - Attributin f CLC dasets using mre detailed infrmatin at natinal level in rder t describe (statistically) the cntent f each CLC plygn in terms f a predefined set f land cver types (measured as percentage cverage). - Substituting the CLC plygn structure with a raster r grid structure: Infrmatin n percentage cverage f varius land cver types and ther cntent (eg number f buildings r length f rads) can be added t the raster/grid cells thrugh verlay with detailed natinal databases. Changes within the raster/grid cells can als be clavculated. The lcatin f features inside raster/grid cells wuld nt be knwn. MnF_EAGLE3rdmeeting_Lisbn_March10_ /10

3 Eurpean Tpic Centre Land Use and Spatial Infrmatin 2.3 Gaps already identified in the exercise f CLC 2006 and imprvements prpsed fr the future (Gerge Buttner) The current status f the CLC 2006 prject was presented: 36 ut f 39 cuntries has finalised their CLC exercise, with a ttal f 33 mnths t cmplete the prject. The majrity f the cuntries used pht interpretatin except Nrdic cuntries that used digital image prcessing, mdeling and ther existing databases in their cuntries t derive CLC, paving the way fr the future f this activity. It has been als stated that it is pssible t derive CLC and CLC changes by cmbining existing natinal datasets and remte sensing / GIS techniques, althugh fr validatin and verificatin it wuld be needed visual interpretatin as well. The grup discussed that 33 mnths f time frame fr develping such a prject is unacceptable, as it is pssible t d it in 5 t 8 mnths if there is a gd pre-rganisatin frm EEA side and the cuntries have the pssibility t plan in advance the effrts t be dedicated t it. The experience frm CLC2006 is that mst f the 30+/- mnths was used t decide t jin the prgramme, write prpsals, have them apprved and find the surces fr the natinal c-funding. The actual prject wrk was in many (mst?) cuntries carried ut in less than 12 mnths. If the time frame fr develping such a prject is reduced, the verificatin prcess dne by the technical team t harmnize the wrk f natinal teams has t be redesigned. Several prpsals t wrk in a mre efficient manner were: - Cncentrate the effrts (and the available budget) n thse areas that have a higher prbability f changing. - Create a ptential change layer with high reslutin imagery: it will nt be 100% autmatic but it will reduce the effrts by fcusing the wrk n ptential areas where changes are ccurring (in Nrway, 50% f the effrts where saved by using this apprach, as cmpared t the EEA riginal estimate fr Nrway), althugh als lking t the rest f the territry. - NRCs need t encurage natinal institutins respnsible fr maintaining datasets f pssible use in CLC-change detectin t add reference year int their infrmatin and databases t make them useful in CLC cntext. 3. SPLINTER SESSIONS FOR PARAMETRIZATION / ATTRIBUTING EXERCISE The grup divided int 2 discussin grups, in rder t achieve a tentative definitin f the classes t be mapped and describe them thrugh an attributing exercise. Splinter grup 1 This splinter sessin was initially tasked with reviewing the definitin f artificial areas and hw they may be described in terms f physical characteristics (pssibly assessed autmatically frm EO data) and use / functin characteristics (frm external surces). The first step was t define what was meant by artificial and the distinctin with urban which may cntain a range f land cver types including water and vegetatin. One f the key characteristics f artificial areas is the degree f sealing caused by buildings and ther surfaces materials (e.g. asphalt and cncrete). The GMES Fast Track Service n Sil Sealing has already delivered a pan-eurpean sealing data set fr 2006 and an update is underway fr It was suggested that nce the sealing degree is knwn it is imprtant t divide this between buildings and ther surfaces and then, extend this infrmatin t include the height f the buildings. The final physical element selected fr describing artificial areas was the pattern r textures f the buildings and surface features within the area f interest. The land use / functinal characteristics f artificial areas are extremely cmplex as they are the fcus fr many different human activities, including multi-functinal features such as buildings which may cntain cmmercial premises n the grund flr and residential abve r areas f asphalt which culd be used as car parks r fr recreatinal activities at different times. A categrisatin f land MnF_EAGLE3rdmeeting_Lisbn_March10_ /10

4 Eurpean Tpic Centre Land Use and Spatial Infrmatin uses fr artificial areas was attempted alng cnventinal lines using natinal experiences. This splinter sessin was then asked t include a cmprehensive set f features t make up a land surface nmenclature at the Eurpean level. The first step was t develp a simple land cver classificatin which wuld give useful distinctins, but which culd als be realistically delivered by autmated r semi-autmated analysis f EO data, as fllws: 1. Artificial (sealed surfaces and buildings) 2. Water (liquid and frzen) 3. Bare nn-sil (expsed rck and sediment) 4. Sil (sediment with a high prprtin f rganic matter) 5. Herbaceus (vegetated area withut wd species, grassland, crps) 6. Shrubs (shrt r sparse wdy vegetatin, heaths and mrs) 7. Trees (dense mature wdland) An apprach, similar t that described abve fr artificial surfaces, was applied t assciate physical and land use characteristics t each f the land cver classes t allw further divisin int mre useful levels. An indicatr f vegetatin amunt wuld be useful in a similar way t the sil sealing data set. The land use categrisatin was extended t cver additinal functins such as agriculture, frestry etc. An example f hw this apprach wuld perate: a herbaceus area which is permanently vegetated and assciated with agricultural land use was labelled as pasture. A key issue was the delineatin f the bjects which are t be labelled by the nmenclature. N MMU had been specified and culd therefre range frm the 25 ha f CLC t the 0.25 ha f the Urban Atlas in current pan-eurpean prducts. As the first is t carse fr many applicatins and the secnd is unmanageable fr EU levels, a cmprmise wuld be required. It was suggested that bjects shuld be hmgeneus based n the MMU, but hmgenus in terms f which characteristics? Ideas were prpsed fr a tw level bject cncept fr the land cver and land use cmpnents, maybe with different MMUs, r unrelated features such as a grid r administrative districts culd be used. Splinter grup 2 In the sessin n agriculture classes the Prtuguese apprach was further discussed in rder t describe CLC classes with the LCCS Meta language, what was wrking quite well. After the discussin n hw t structure the main classes, a prpsal f a use riented descriptin was cmpared with a strict land cver descriptin. The grup decided t strictly divide land cver and land use cmpnents f classes (currently mixed in CLC definitin) and fllw the land cver descriptin cnsidering additinal attribute(s) n land use. This wuld allw mre flexibility f linking/cmparing CLC classes with ther nmenclatures. Additinally, it was discussed hw t describe (and recrd) cmpsitin inside f an individual CLC plygns and it was decided that the base land cver elements shuld be part f the descriptin as statistical infrmatin (percentages). First, it wuld imprve current infrmatin deficiencies caused by 25ha MMU as well as it wuld allw better understanding f CLC class cntent in different MSs/regins. Further descriptin f the plygn with additinal attributes was nly cnsidered n the level f the whle plygn, nevertheless prs and cns were discussed but nt clsed. A presentatin f the apprach fllwed in Decver was given as an example t take int cnsideratin fr further develpments. Ging back t the results, it was decided t discuss the base land cver classes cmpsitin and additinal attributes needed fr all CLC agriculture classes descriptin. Based n that exercise, the final prpsal fr base land cver classes and additinal attributes wuld lk like as the lists belw. Ptential MnF_EAGLE3rdmeeting_Lisbn_March10_ /10

5 Eurpean Tpic Centre Land Use and Spatial Infrmatin data surces t gather these infrmatin has been discussed t and satellite image prcessing has been identified as ne f the effective surces (but nt necessary exclusive) t fill base land cver classes/elements infrmatin. 1) Cnsidering base land cver classes: Vegetated Herbaceus Wdy Trees shrubs Lichen and mses Nne vegetated Artificial Build up Nn built up Natural Rck Sil Sand Mud Salt Water Snw and ice Water bdy 2) And cnsidering the attributes, anther list was develped: Vegetatin cverage Hetergeneity Height Management Use Water cntent Irrigatin Permanent, nn permanent, rtatin Species Vine Olive Fruit and berries Rice Others 4. GUIDED DISCUSSION TO DEVELOP RECOMMENDATIONS FOR GIO A separate dcument is prvided summarizing the sessin regarding GIO, in rder t cmmunicate the utcmes f the sessin t the EEA. The main cnclusins f the sessin are the fllwing nes: General willingness t supprt anther CLC update if certain cnditins are met. Need fr a detailed planning and timing f the exercise befre the prject start. Timely infrmatin t the cuntries abut what is expected frm them. A fully funded exercise wuld be needed t ensure the implementatin f the prject in the envisaged time table. Questin abut the EO data reference date f the update (2009, 2010, 2011). Flexibility f EEA with respect t the final deadline (mid d2012) MnF_EAGLE3rdmeeting_Lisbn_March10_ /10

6 Eurpean Tpic Centre Land Use and Spatial Infrmatin Prpsal t develp a change indicatr map t supprt land cver change mapping. 5. CONCLUSIONS AND NEXT STEPS The splinter sessins as well as the sessin cncerning GIO were resumed t achieve a cmmn understanding and define the steps frward. The fllwing pints were agreed: - CLC exist and it cannt be changed cmpletely (and it is nt the purpse fr the time being; results f the wrk develped shuld be seen t take such a decisin and currently, the whle prcess is just in the transitin phase), s building upn what is existing will be t btain mre infrmatin abut what can be fund inside the Crine plygns: attributin and parameterizatin - Wrking in this directin will allw an assessment f the variability ver CLC classes amng the different cuntries and check als hw CLC is implemented in the different cuntries (based n the class cntent). Backwards cmparability will be als ensured. - In the future, it culd be develped a mre cmplex mdel which interlinks land use and land cver, and als discuss abut imprving gemetry; but this issue will imply a fundamental change and cnsequences fr backwards cmparability, s it shuld be discussed in detail in the upcming meetings. - A prpsal fr geland2 develpments was raised (but nt unifrmly agreed): t create a land cver map fr Eurpe with the 7 r 10 exhaustive and mutually exclusive land cver classes that the grup is ging t agree n and imprve existing infrmatin n sil sealing. Next steps: There will be three main activities t be develped in the cming mnths: - Ppulating CLC plygns with fundamental classes. Wh has cmmitted t d it? Nrway: will d it based n the 2 lists f land cver types being discussed in the splinter sessins (but adjusting fr data availability in Nrway) and prducing a Nrwegian list f maximum 10 basic land cver categries Austria: will d it fr sme test sites Hungary: Tkaj regin United Kingdm Czech Republic: will d it and will als add pssible attributes that culd be derived frm satellite images Luxemburg (mst prbably) - Attributin f the fundamental classes (expected cntributin frm all the grup): The bjective f this activity is t develp a whle list f attributes that will define each f the pure land cver classes decided. A separate dcument t wrk n, cntaining basically the discussed pints in the splinter sessin, will be distributed t the whle grup. By the end f April mid May 2010, cmpilatin and summary f the feedback received frm all the grup: Pending discussin nce results btained cncerning the applicability t existing Crine and its traceability. - Mdel the utcmes f bth exercises: Prtugal is ging t wrk n this item. MnF_EAGLE3rdmeeting_Lisbn_March10_ /10

7 Eurpean Tpic Centre Land Use and Spatial Infrmatin Nt explicitly mentined during the meeting but a crucial item t take int accunt fr the upcming activities is t determine, cnsidering the utcmes f the exercises described abve, which is the final purpse f the analysis undertaken and prvide specific reasns cncerning why it has dne in this way. It will be als imprtant t decide the subsequent applicatins f these utcmes (i.e. cmparisn f natinal analysis t define at the end an EU standard f fundamental classes r cmparisn f the results btained in the different cuntries t check the hmgeneity f CLC between them, amng thers). AOB Next meeting: is ging t be scheduled arund 20 th f September Ljubljana culd be a candidate place. Prpsal fr making a publicatin with all the results already btained by the grup. MnF_EAGLE3rdmeeting_Lisbn_March10_ /10

8 Eurpean Tpic Centre Land Use and Spatial Infrmatin ANNEX Technical details f the presentatins Translatin prcess f the CLC 3 rd level classes int FAO nmenclature. Vasc Nunes The bjective f the wrk dne was the translatin f the CLC nmenclature int FAO s Land Cver Meta language (LCML) in rder t test hw CLC classes can be described using FAO s tls. This translatin was made using FAO s Land Cver Classificatin System (LCCS) sftware (versin 3 still being tested) and the apprach was t input main class descriptrs enugh t discriminate between CLC classes, as ppsed t inputting all descriptrs included in CLC class definitins. Several items shuld be taken int accunt fr this translatin, namely the land cver elements, their characteristics (attributes and prperties) and their layering dispsitin. Difficulty and ambiguity f translatin depend n the CLC class yu are wrking with and it ranges frm a direct translatin t a very questinable ne. Sme cnclusins were: - the Land Cver Meta Language is able t describe in a very strighfrward way mst f the CLC classes; - there is mre than ne crrect frm t describe a CLC class using LCCS; - its nt clear when t stp in detailing class descriptins; - mst CLC classes culd use smaller descriptins; - cmplex classes like (242, 313, 324, etc) are mre difficult t translate; - sme imprvements in the LCCS sftware may reslve several encuntered difficulties; It has been discussed the aim f this exercise and the fields this wrk can be used, and it has been agreed that it can explain in a mre detailed way the cntent f the CLC classes and t really check the cmparability amng the different natinal teams. Based n this type f studies, the variatins and differences acrss Eurpe regarding the definitin f the land cver classes, which is really imprtant fr the parameterizatin exercise that wuld aim t btain a single definitin at Eurpean level. Translatin f existing CLC int bject riented data mdels Guillerm Villa Althugh the best way t represent a data mdel is a UML diagram, experience in grup discussins in Spain has shwn 2 limitatins: - Difficulty t have an verall view f the mdel when displayed n the screen - Many dmain experts participating in the discussins are nt familiar with UML symbls Fr this reasns, a simplified view f the data mdel in an Excel sheet was sent t the grup previus t the meeting, and is presented here. In this Excel sheet we can see: 1) The prpsed land cver classes, arranged in a hierarchical way (a taxnmy ). The prpsal is t use CLC standard 3 level nmenclature as starting pint. 2) The prpsed land cver elements, real wrld elements that make up land cver classes, arranged in a hierarchical way. The prpsal is t start with terms that appear in the definitins f CLC classes (buildings, vegetatins, etc ) MnF_EAGLE3rdmeeting_Lisbn_March10_ /10

9 Eurpean Tpic Centre Land Use and Spatial Infrmatin 3) The prpsed attributes, imprtant characteristics f land cver classes and land cver elements. The prpsal is t start with terms that appear in the definitins f CLC classes (height, irrigated, etc ) 4) Which land cver classes are part f each land cver class When ding the exercise, it has been seen that sme CLC subclasses already in place shuld disappear and the infrmatin shuld be integrated int the upper class as an attribute (e.g. abandnment, under cnstructin, types f frest, ), and infrmatin that shuld be prvided as a percentage instead f a new class detailing the degree f cverage, fr example. If the grup feels the need t add mre details, a very lng list f Land cver classes, land cver elements and attributes fr bth can be fund if the dcument CORINE land cver nmenclature illustrated guide. Nevertheless, grup shuld take int accunt that Inspire is lking fr simple data mdels that can be agreed n by all cuntries. At natinal level, each cuntry can decide t add mre classes r attributes in the natinal prfile, but at Eurpean level it shuld be reached an agreement in rder t ensure harmnisatin and cmparability. Several questins arused frm the presentatin and were discussed, such as a) hw tw plygns then can be split if yu nly have different attributes but the same general label, r b) the relatin f this exercise with the MMU (if yu strictly apply MMU, then it seems that there is n difference between attributes r classes), r c) if Crine plygns culd be described nly using statistical data that will be available at Eurpean level by grid cells f 100*100m. Depending n the purpse f the analysis, there are 2 ptins (explained by Nrway): - Overlapping CLC with mre detailed infrmatin at natinal level in rder t knw what is really inside a CLC plygn (percentage and lcatin). - Overlapping the mre detailed infrmatin with raster r grid structure: infrmatin n percentages and n changes in the percentages will be available, but the lcatin wuld nt be knwn (it will be nly pssible t present a unique type f infrmatin each time yu query the database). Gaps already identified in the exercise f CLC 2006 and imprvements prpsed fr the future Gerge Buttner CLC2006 has fficially finished in mid-february 2010 in 36 cuntries (ut f ttal 39 planned). CH and UK are still wrking, and plan t finish this year. GR is nt participating. The ttal duratin f technical implementatin was 33 mnths, which is hardly acceptable fr the EEA. Main prblems during implementatin were: 1. Lng administrative preparatin, including financial cmmitment is sme cuntries (e.g. DE, IT..). 2. Elngated implementatin time in sme cuntries due t difficulties in prviding natinal cntributin (e.g. AT, HU, UK ). 3. Lng GIS integratin phase (several mnths) in sme cuntries (e.g. ES, NO..) There are psitive examples f fast (5-8 mnths) implementatin in sme larger cuntries: FR, PL, TR... Mst cuntries applied CAPI technlgy as suggested in the Technical Guidelines. Especially Scandinavian cuntries applied different cmbinatins f digital image prcessing f satellite images, GIS integratin f existing natinal data sets and phtinterpretatin. MnF_EAGLE3rdmeeting_Lisbn_March10_ /10

10 Eurpean Tpic Centre Land Use and Spatial Infrmatin Being already the 3 rd CLC exercise, there were n critical prblems with the applicatins f the nmenclature. Sme typical, frequently ccurring difficulties: Nn-cnsequent separatin f pastures (231) and natural grasslands (321); nn-cnsequent separatin f arable land (211), pastures (231) and cmplex cultivatin (242); irrigated land (212) was an used incnsistently (nt nly arable land is irrigated..). The 100 m psitinal accuracy was kept rather well (lwer accuracy in sme cuntries / regins). Verificatin f natinal CLC-Changes datasets was as imprtant issue: t achieve harmnised applicatin f mapping rules and nmenclature, t prvide cmparable datasets by the cuntries, and t assure thematic quality f database. N cnceptual prblems in change mapping were bserved. The verall 5 ha rule was applied prperly and did nt verlad the natinal teams. Technical change was used accrding t purpse t cmpensate the effect f tw different MMUs. In sme cuntries technical change was used als t take care f mistakes in CLC2000. Sme typical prblems: Nt always the real change was mapped. Cnsidering the frequent change types mapping frest grwth was the mst difficult and subjective. The magnitude f ttal changes (yearly percent ttal change) is belw 1 % except PT. Cnsidering the experiences f Scandinavian cuntries the future f Eurpean land mnitring can include: Cmbinatin f existing natinal datasets and RS/GIS; generalisatin fr the purpses f EEA RS-based visual quality cntrl MnF_EAGLE3rdmeeting_Lisbn_March10_ /10