introductory remote sensing•remote sensing is the art and science of acquiring information about...
TRANSCRIPT
Geob 373
INTRODUCTORY REMOTE SENSING
Landsat 7 15 m image highlighting the geology of Oman
http://www.satimagingcorp.com/gallery-landsat.html
THE MACKENZIE RIVER IN CANADA SEEN FROM SPACE.
THE LENA RIVER IN RUSSIA
ADDING COLOUR TO THE UNSEEN
The colours we see.
Green
RedBlueRadio
wave
Infra red
The ‘colours’ we don’t
ASTER 15 m SWIR image, Escondida Mine, Chilehttp://www.satimagingcorp.com/satellite-sensors/aster.html
ASTER 15 m SWIR image, Mexicali
ASTER 15 m image, Las Vegas
MODIS 50 m hyperspectral image, Alaska
http://airbornescience.nasa.gov/instrument/instruments.html
GOALS OF THE COURSE • Overview of basics of remote sensing:
• Electromagnetic spectrum (energy), spectral responses of objects (e.g., trees, buildings, crops)
• Platforms/Sensors: where / how they capture the energy
• How this energy gets converted into images (A2D)
• Development of technical / theoretical skills for reading, enhancing and processing remotely sensed data in ArcMap (DIP)
• Use of remotely sensed imagery in (e.g.) environmental change detection, urbanization, desertification, deforestation, forest fire monitoring, natural hazards
• Become aware of the uses of remotely sensed data in a Geographic Information System
GOALS OF THE COURSE• At the end of the course you should be able to, for a particular
environmental problem (e.g., examining the effects of mountain pine beetle in BC):• Determine what data is available,
• identify what data is relevant (resolution, spectral response, temporal aspects),
• load and process data in remote sensing software (georectification, enhancement, classification),
• conduct change analysis, and
• understand error.
• That is, know which imagery can be applied to which environmental problem, and what information you can obtain from the analysis.
COURSE PARTICULARS
• Web site: http://www.geog.ubc.ca/courses/geob373• Contains:
• Syllabus (marking scheme, etc.)• Class and lab schedule• Lab instructions• Project description
• Laptops okay, but, please
WHAT IS REMOTE SENSING?
• Remote sensing is the art and science of acquiring information about the Earth's surface without actually being in contact with it. This is done by sensing and recording reflected or emitted energy and processing, analyzing, and applying that information.
WHAT IS REMOTE SENSING?• Platforms
• Data types
• Analog (mainly older aerial photographs, some very old satellite imagery)
• Digital (satellite images, now aerial photography as well, LIDAR, RADAR)
• Science: Physics (in particular for RADAR)
• Art: Subjective interpretation
• Data qualities
• Fine resolution--Large scale analyses
• Coarse resolution--Small scale studies
• Data sources: Visible light (sun, lasers), ‘heat’ (IR), radio waves (radar)
• and much more.
PLATFORMS• Different platforms (the
object that holds/contains the remote sensing device) are used, depending on the budget and scale of the study.
Drone
AERIAL PHOTOGRAPHY
• Stereo-effect: pairs of images that are displaced produce a 3-D effect.
• Allows for measuring elevation, and for correcting for the distortions created by elevation (and perspective projections).
COLOUR AERIAL PHOTOGRAPHS
Shinnecock Bay, Long Island, NY highlighting submerged aquatic vegetation
INFRARED AERIAL PHOTOGRAPH
Airborne thermal IR (25 cm resolution) of homes highlighting energy loss
http://www.imagingnotes.com/go/article_free.php?mp_id=181
OBLIQUE AERIAL PHOTOS
Eagleview
SATELLITE IMAGERY: OCEAN MONITORING
Eddies off of Haida Gwaii
SeaWiFS (1 km) data June 13, 2002.
http://earthobservatory.nasa.gov/IOTD/view.php?id=2536
DROUGHT MONITORING
JULY 2001 JULY 2002LANDSAT THEMATIC MAPPER (30 m) (SOURCE: CCRS 2002)
(Healthy vegetation is bright red)
MODIS imagery (200 m) showing Myanmar before
and after being hit by a cyclone.
DISASTER MONITORING
http://movingimages.wordpress.com/2008/05/
LIGHT DETECTION AND RANGING
Forest canopy (1st return)
Using many rapid small bursts of laser light, an aircraft-borne apparatus records reflection
from multiple sources.
Ground surface (last return)
LIDAR
Archaeology
Oceanography
PHODAR?• PhoDAR is a portmanteau word that joins the words “photography” and “LiDAR.” The
technology creates 3D point clouds by processing high-res imagery.
• PhoDAR is another name for structure from motion (SfM) photogrammetry. It’s misleading to call this 3D mapping process “PhoDAR,” since it doesn’t use ranging hardware as the “DAR” part of the name would indicate. Like other photogrammetric methods, it uses simple camera hardware.
RADAR – MONITORING SEA ICE
(30 m)
LECTURE REVIEW
• This is just a brief overview of the various sensors and applications that we will cover in greater detail throughout the course.
• The notes will supplement the text, while the labs will complement the lecture material by exposing you to real-world data and applications.