Reference data, its importance in remote sensing, its types, successful application of RS and how we can collect reference data.

1. REFERENCE DATA AND ITS
IMPORTANCE IN R.S

2. Hafiz Ali Raza (SS15-20)
Hafiz Anas (SS15-12)
Hiba Shahid (SS15-13)
Maham Irfan (SS15-15)
GROUP MEMBERS:

3. REFERENCE DATA
Reference data involves the
collection of measurements or
observations about objects,
areas or phenomena that are
being remotely sensed.
These data can be taken on any of a
number of different forms and
may be derived from a number of
a sources.
Reference data involves field
measurements of temperature and other
physical and chemical properties of
various features. Diavik Diamond Mine, Canada

4. Importance of Reference data
in Remote Sensing
Satellite Image Airborne ImageGoogle Earth Image

5. Importance of Reference Data in R.S
• Provide assistance in analyzing and interpreting the remotely sensed
data.
• To calibrate a sensor.
• Verification of interpreted data through Reference data.
• To build the relationship between surface features and localities
through satellite photographs.
• It may be the single most important factor in accuracy assessment,
since an assessment will be meaningless if the reference data cannot
be trusted.

6. Types of Reference data
There are two main types of reference data:
1) Time Stable measurements
2) Time Critical measurements
1) Time Stable Measurements
Time stable measurements are involved when the materials under
observation don’t change appreciably with time.
For example Geological applications, Archeological sites etc.

7. 20172000
1: Badshahi Mosque
Examples of Time Stable:

8. 2. Great Pyramids of Giza
1930 2011

9. 3. Saif-ul-Malook Lake
2006 2017

10. 4. Taj Mahal Agra
2000 2017

11. 5. Eifel Tower Paris
2001 2017

12. 2) Time Critical Measurements
Time critical measurements are those made in cases
where ground conditions change rapidly with time.
For example: The analysis of water pollution events,
Earthquakes etc.

13. Examples of Time critical:
1. Flooding
September 8, 2009 December 8,2010

14. 2. Earthquake
Balakot

15. Earthquake
September 22, 2002 October 9, 2005

16. 3. Tornado
Illinois Washington

17. 4.Duststorm

18. Multi Approach in Reference Data
1. Multi-stage
2. Multi-level
3. Multi-phase
4. Multi-spectral
Successful Applications of RS:

19. 1.Multi-stage:
Data should be procured whenever possible from different platforms.
Landsat 8 Google Earth

20.  Space Borne
 Aerial
 Ground Level
2. Multi-level:
Data collected at various distances
from the Earth’s surface.

21. 3. Multi-phase:
Some data correlate with one another and also with other
remote sensing data.
Middle phase Final phaseInitial phase

22. 4.Multi-spectral:
Data collected over various regions of the spectrum.
Red (0.63-0.69) um NIR (0.76-0.90) um False Color IR (4,3,2)
Landsat 5

23. HOW TO COLLECT REFERENCE DATA
There are two main methods for the collection of
reference data:
1. Aerial photography
2. Ground Based Measurements

24. Aerial photography is the taking of images from an aircraft or
other flying object at different altitudes.
Platforms for aerial photography include aircrafts, helicopters,
drones etc.
1. Aerial photography
Aircraft DronesHelicopter

25. Image A Image B
Image B is reference data for Image A and Image C is reference data for Image B
Aerial Photography
Landsat image Google earth image
Image C
Drone Image

26. 2. Ground based measurements
There are two types of ground based
reference data.
(i) In field.
(ii) In laboratory.

27. (i) In field:
In field we can take reference data in various aspects.
For example,
Meteorological measurements, water level
in rivers, soil texture, crop phases etc.

28. (ii) In laboratory:
In laboratory we can take
reference data in two ways.
a. Chemical tests.
b. Spectroscopy.
a. Chemical tests:
With the help of chemical tests we
can check the chemical composition
of soil, moisture in soil, pH level of
water and soil. Further we can also
extract information about minerals
hidden beneath the surfaces of earth.

29. b. Spectroscopy:
• In Laboratory spectroscopy, artificial
sources of energy might be used to
illuminate objects under study.
• In the laboratory, other field
parameters such as viewing
geometry between object and
sensor are also simulated.

30. References:
Book:
• Remote sensing and image interpretation by
Thomas M.Lillesand,Ralph W.Kiefer,Jonathan W.Chipman.
Internet:
• www.sciencedirect.com/science/article/pii/S1110982315000332
• www.slideshare.net
• http://www.mdpi.com/2072-4292/8/2/109/htm
• https://www.fs.fed.us/pnw/pubs/journals/pnw_2012_anderson002.pdf
• www.researchgate.net
• www.colorado.edu
• www.globalspec.com

31. Thank you!