Proposed National Geodetic Datum in Palestine Dr Ahmad

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Proposed National Geodetic Datum in Palestine Dr Ahmad Taha Diploma, B. A, M. Sc

Proposed National Geodetic Datum in Palestine Dr Ahmad Taha Diploma, B. A, M. Sc & Ph. D (Nottingham University-UK) An-Najah National University Geography Department, Nablus, Palestine Eng. Ahmed Madi and National Geodetic Team Palestinian Land Authority The 11 th International Congress of GIS and Geo. Space Applications, Geo-Tunis LAICO Hotel: Yasmine Hammamet, Tunisia from 25 to 29 April 2017 1

Presentation Structure Overview Evaluation of Control Points Proposed National Geodetic Datum in Palestine Conclusions

Presentation Structure Overview Evaluation of Control Points Proposed National Geodetic Datum in Palestine Conclusions Acknowledgments 2 2

Overview British Survey of Palestine during 1920 - 1948 results in the establishment of

Overview British Survey of Palestine during 1920 - 1948 results in the establishment of horizontal and vertical networks Horizontal Network: consists of several thousands of points distributed in Palestine in different orders. 3 Chain was used in measurement of baseline Theodolite was used in measurement of angles Vertical Network: Precise leveling – few points Trigonometric leveling – elevation for horizontal points 3

Overview: Survey of Palestine The Major Triangulation system in Palestine (left) and measurement taken

Overview: Survey of Palestine The Major Triangulation system in Palestine (left) and measurement taken from point 2 M of the Palestine Major triangulation base line (right). • Palestine • 426 X 109 km 4 • 27, 365 km 2 4 Source: http: //www. pef. org. uk/monographs/the-survey-of-palestine-under-the-british-mandate-1920 -1948 (14 -

Overview: Survey of Palestine • The Major Triangulation points in West-Bank (32 points -

Overview: Survey of Palestine • The Major Triangulation points in West-Bank (32 points - Left) and Second order points (≈300 points - Right). From North to South ≈137 km and East West ≈57 km. • West Bank: • 5, 565 km 2 5 • 20. 33% • Gaza • 364 km 2 • 1. 33% 5

Overview: Survey of Palestine Available Bench mark points in north of West-Bank (≈ 60

Overview: Survey of Palestine Available Bench mark points in north of West-Bank (≈ 60 points -left) and British trigs (6, 600 point) & Jordanian trigs (1, 450 point) (right). 6 6

Evaluation of Control Points West Bank Check conducted by Surveying Department Team. About 40

Evaluation of Control Points West Bank Check conducted by Surveying Department Team. About 40 points used. Network RTK (VRS)system used. Maximum error: E=1. 90 m, N= 0. 70 m 7 Error Range: E=0. 80 m, N= 1. 00 m d. E & d. N 0. 8 0. 6 0. 4 0. 2 d. N 0 -2. 5 -2 -1. 5 -1 -0. 5 0 -0. 2 -0. 4 7 -0. 6 0. 5 1

Evaluation of Control Points Local Check (in Nablus District) GNSS receiver in Real Time

Evaluation of Control Points Local Check (in Nablus District) GNSS receiver in Real Time Kinematic (RTK) was used. 8 8

Evaluation of Control Points British Network Assessment of Trig Points: Station: Point: GPS Sat.

Evaluation of Control Points British Network Assessment of Trig Points: Station: Point: GPS Sat. 430 G 9 9 956 X Distance: 2, 788. 766 m 8 Precision, H: 1 cm Diff. Fix E= 10. 5 cm GLN. Sat. 5 V: 1. 3 cm N= 4. 4 cm H= 7. 3 cm

Evaluation of Control Points British Network Assessment of Trig Points: Station: Point: GPS Sat.

Evaluation of Control Points British Network Assessment of Trig Points: Station: Point: GPS Sat. 1017 X 10 430 G Distance: 2, 769. 349 m 8 Precision, H: 0. 2 cm Diff. Fix E= 0. 4 cm GLN. Sat. 5 V: 0. 5 cm N= 0. 2 cm H= -20. 6 cm

Evaluation of Control Points British Network Assessment of Trig Points: Station: Point: GPS Sat.

Evaluation of Control Points British Network Assessment of Trig Points: Station: Point: GPS Sat. 1017 X 11 1059 X Distance: 2, 214. 298 m 8 Precision, H: 0. 2 cm Diff. Fix E= 42 cm GLN. Sat. 5 V: 0. 5 cm N= 16. 9 cm H= 19. 7 cm

Evaluation of Control Points Jordanian Network Densification of the British Horizontal Network using Theodolite

Evaluation of Control Points Jordanian Network Densification of the British Horizontal Network using Theodolite Station: Point: GPS Sat. 12 430 G Fix 12 1568 BC Distance: 372. 418 m 7 GLN. Sat. 0 Precision, H: 1. 8 cm V: 0. 9 cm Diff. N= 32. 2 cm E= 3. 7 cm

Evaluation of Control Points During Israel Occupation Densification of the British Horizontal Network using

Evaluation of Control Points During Israel Occupation Densification of the British Horizontal Network using Traverse Accumulated error 13 Allowed error in traverse of 3582. 87 m is 2. 35 m Station: 558 C Point: 601 T Distance: 1, 860. 936 m GPS Sat. 13 7 Fix GLN. Sat. 5 Precision, H: 0. 3 cm V: 0. 6 cm Diff. N= 6. 8 cm E= 0. 1 cm

Evaluation of Control Points During Palestinian Authority Still use traverse Start using GPS Every

Evaluation of Control Points During Palestinian Authority Still use traverse Start using GPS Every surveyor measures a polygon in his area 14 Israel GPS companies compute 7 transformation parameters Bethlehe Example: Ramallah and Bethlehem parameters 14 Parameter Ramallah dx 121. 451 dy 114. 142 dz -284. 684 Rx -11. 1499 Ry -8. 56249 Rz -5. 04769 scale 8. 8471 m 123. 649 67. 957 -406. 173 -11. 6318 -5. 32853 -5. 62189 22. 2106 Units m m m sec. ppm

Evaluation of Control Points How errors affect our life? Cause large errors in property

Evaluation of Control Points How errors affect our life? Cause large errors in property boundaries and accumulated errors in engineering projects. 15 15

Proposed National Geodetic Datum in Palestine There is a serious need to establish a

Proposed National Geodetic Datum in Palestine There is a serious need to establish a precise National Geodetic Network (Palestine Grid 2017 – PG 17) to replace the traditional networks with a superior GPS-based solution. 16 16

Proposed National Geodetic Datum in Palestine Previous Work In 1999, Ordnance Survey (OS) team,

Proposed National Geodetic Datum in Palestine Previous Work In 1999, Ordnance Survey (OS) team, from the U. K. , have a reconnaissance visit and they recommended to establish a new geodetic network for West Bank and Gaza. 17 In 2000, Norway Mapping Palestine project: Measured two polygons: one in Nablus and the other in 17 Ramallah. The result of this work was a list of adjusted coordinates based on the current coordinates system. They recommended to carry on similar work in Jenin, Tulkarim, Qalqilia and Hebron.

Proposed National Geodetic Datum in Palestine Background: GPS provides with 3 D Cartesian coordinates

Proposed National Geodetic Datum in Palestine Background: GPS provides with 3 D Cartesian coordinates in WGS 84 system (XWGS 84, Y WGS 84, Z WGS 84). Define reference Ellipsoid. Transform GPS coordinates to Local system (X 18 LOCAL, Y LOCAL, Z LOCAL). Need to compute 7 transformation parameters. Define a map projection. Convert Local coordinates to Grid coordinates (E, N, h). Need to define projection parameters. We need a Geoid undulation datum to covert ellipsoidal height (h) to orthometric height (H). 18

Proposed National Geodetic Datum in Palestine Reference Ellipsoid parameters: a: semi-major axis b: semi-minor

Proposed National Geodetic Datum in Palestine Reference Ellipsoid parameters: a: semi-major axis b: semi-minor axis or f: flattening , f=(a-b)/a f expressed as 1/f 19 Old System: Clarke 1880 Palestine (a=6378300. 789 m, 1/f= 293. 466) New System: WGS 84 datum surface (a = 6378137. 00 m, 1/f=1/298. 257223563) 19

Proposed National Geodetic Datum in Palestine Bursa-Wolf Model (Helmert Transformation) Measure several points: 1

Proposed National Geodetic Datum in Palestine Bursa-Wolf Model (Helmert Transformation) Measure several points: 1 st & 2 nd order Compute 7 transformation parameters 3 translation: ∆X, ∆Y, ∆Z 3 rotation: Rx, Ry, Rz Scale: S 20 20

Proposed National Geodetic Datum in Palestine Projection Type Old System: Cassini Soldner New System:

Proposed National Geodetic Datum in Palestine Projection Type Old System: Cassini Soldner New System: Transverse Mercator which is best suited for north–south areas like Palestine 21 Central Meridian (main datum point): as in the old projection, crosses through Jerusalem (82 M) New Zero at 34˚ 00’ 00”E, 29˚ 00’ 00”N to avoid negative values in the south Main grid point values False Easting (m): 170251. 5545 (old), ≈114600. 00 (New) False Northing(m): 126867. 9090 (old), ≈305000. 00(New) New Grid Scale factor: 1. 0000067 21

Proposed National Geodetic Datum in Palestine 22 22

Proposed National Geodetic Datum in Palestine 22 22

Proposed National Geodetic Datum in Palestine Vertical Datum Can be either Ellipsoid or Geoid

Proposed National Geodetic Datum in Palestine Vertical Datum Can be either Ellipsoid or Geoid GPS measures Ellipsoid Height Need Geoid Undulation: Global Models (EGM 08 … ) integrated by 23 BMs 23

Proposed National Geodetic Datum in Palestine Field work: Stage 1: Building First Order Control

Proposed National Geodetic Datum in Palestine Field work: Stage 1: Building First Order Control Points Measure several control points (30 -40 km) distributed all over West-Bank using GPS. (proposed 6 points). Static GPS for 8 hours. 24 Tie into the International Terrestrial Reference Frame (ITRF 2008). These points will form the first order control points of the new system. Repeat measurement each month (for 6 months) to check local movement. Elevation carried out by precise leveling in least squares solution from original benchmarks. ( 3 d control) 24

Proposed National Geodetic Datum in Palestine Stage 2: Densification of Second Order Control Points

Proposed National Geodetic Datum in Palestine Stage 2: Densification of Second Order Control Points Proposed 10 points in each district (110 points) Densification of passive and active stations. Static GPS for 2 hours. The passive stations consists of publicly accessible control 25 points. The active stations consists of permanent GPS reference stations. The data from the active stations can be used to produce a real time positioning through a Virtual Reference Station System (VRS) Elevation carried out by precise leveling in least squares solution from original benchmarks. ( 3 d control) 25

Proposed National Geodetic Datum in Palestine Stage 3: Measuremnts of BMs (Height Reference System

Proposed National Geodetic Datum in Palestine Stage 3: Measuremnts of BMs (Height Reference System - HRS) Measure available Bench Marks using Static GPS for 2 hours. The densification data will be from global Geoid model ( EGM 2008) 26 The integration will be done using finite elements methods to make the global models fit the local datum of Palestine. The Palestinian areas will be divided into patches to define local datum. Interpolation using small elements with continuity conditions. Software : www. dfhbf. de 26

Proposed National Geodetic Datum in Palestine What have been done so far? Form a

Proposed National Geodetic Datum in Palestine What have been done so far? Form a National Geodetic Team to decide new surveying standards and to organize all surveying issues in Palestine. 27 Start Planning the location of the control points. Start gathering some observations for evaluation purposes. Fund of $1. 7 millions from State of Palestine for Surveying Department to establish the New Geodetic Datum. 27

Proposed National Geodetic Datum in Palestine What have been done so far? A home

Proposed National Geodetic Datum in Palestine What have been done so far? A home made software called Najah Surveying Suite (NSS) has been developed to compute the 7 transformation parameters using least squares. 28 28

Conclusions Large errors up to 190 cm in the horizontal control points and up

Conclusions Large errors up to 190 cm in the horizontal control points and up to 20 cm in the vertical controls. Accumulated errors can affect our life seriously and caused large errors of more than 1. 0 m. 29 Solution for such errors can be through the establishment of new National Geodetic Datum in Palestine. Parameters of the proposed Palestine Grid 2017 (PG 17) have been determined. Planning and preparation stages have been started. 29

Acknowledgments I would like to thank the National Geodetic Team for their corporation. Special

Acknowledgments I would like to thank the National Geodetic Team for their corporation. Special thanks goes to Dr Ahmad Ra’fat for his unlimited support. 30 Many thanks go to the wonderful team of Taha Surveying, especially Mr Ashraf Qadus, for the hard work in the local data collection. 30

National Geodetic Team: 31 Dr Ahmad Taha Dr. Ghadi Younis Eng. Ahmed Madi 31

National Geodetic Team: 31 Dr Ahmad Taha Dr. Ghadi Younis Eng. Ahmed Madi 31 Eng. Saed Idais Eng. Ghada Awad Eng. Sameh Khleef Eng. Sadeq Abu Zanoon Eng. Hamza Teerawi Eng. Mohammad Maraheel Mr. Bassam Nada Mr. Saber Bodeer

32 Thank you 32

32 Thank you 32