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Beginner’s GIS Biodiversity Informatics Training Workshop June 2012

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Beginner’s GIS. Biodiversity Informatics Training Workshop June 2012. Outline. What is GIS GIS & Map Fundamentals Spatial Data Types Data Formats Software DEMO/Exercises. What is GIS?. GIS = G eographic I nformation S ystem(s) - PowerPoint PPT Presentation

TRANSCRIPT

Page 1: Beginner’s GIS

Beginner’s GIS

Biodiversity Informatics Training Workshop

June 2012

Page 2: Beginner’s GIS

Outline

• What is GIS• GIS & Map

Fundamentals• Spatial Data Types• Data Formats• Software• DEMO/Exercises

Page 3: Beginner’s GIS

What is GIS?

GIS = Geographic Information System(s)

GIS is a collection of computer hardware, software, and geographic data for capturing, managing,

analyzing, and displaying all forms of geographically referenced information.

Environmental Systems Research Institute (ESRI), 2007

Page 4: Beginner’s GIS

What is GIS?

An “image” with attribute information

Page 5: Beginner’s GIS

What is GIS?

Tool to make complex patterns simple

Page 6: Beginner’s GIS

What is GIS?

Environment for integrating diverse data

Page 7: Beginner’s GIS

Overview of spatial data

Raster and vector data collide

Page 8: Beginner’s GIS

Overview of spatial data

Page 9: Beginner’s GIS

Points, lines, and polygons

Vector data

Page 10: Beginner’s GIS

Vector data

• Shapefiles are common vector format of GIS data

Shapefiles consist of 3 main components:*.shp – main file stores geometry*.shx – index of geometry*.dbf – database of attributes

Page 11: Beginner’s GIS

Shapefiles may also have:*.prj – plain text file of projection*.sbn and *.sbx – spatial index of features*.atx – index of attributes*.shp.xml – metadata

Vector data

Page 12: Beginner’s GIS

Resolutione.g. 4 x 4 km

Raster Data

Page 13: Beginner’s GIS

General data issue: spatial scale

Decrease in resolution

Increase in extent

Spatial scale has two elements: resolution and extent

Resolution

Ext

ent

In practice, resolution and extent tend to beinversely related

Page 14: Beginner’s GIS

Resolution= cell size

Raster Data

Page 15: Beginner’s GIS

15 KM pixel

Page 16: Beginner’s GIS

7.5 km per pixel

Page 17: Beginner’s GIS

4.5 km per pixel

Page 18: Beginner’s GIS

1 km per pixel

Page 19: Beginner’s GIS

Raster data - interpolation

Raster Data

Page 20: Beginner’s GIS

Inverse distanceweighting

Kriging PolynomialsOr Spline

Raster data - interpolation

Raster Data

Page 21: Beginner’s GIS

Inverse distanceweighting

Kriging PolynomialsOr Spline

Raster data - interpolation

Raster Data

• Using linear-weighted set of samples (greater the distance, the less influence on output raster value)

• Good for dense sampling

• Statistical method that fits a function to a radius of points, assuming a spatial correlation in distance or directionality

• Interpolated surface do not pass through sample sites

• Many different types

• Uses a mathematical function to create a minimize overall surface curvature

• Sample points pass through surface

• Best for variables like T

Page 22: Beginner’s GIS

Raster data - interpolation

Raster Data

Page 23: Beginner’s GIS

Environmental Data: conversion to raster

Weather station records (vector point data)

Interpolated raster climate surfaces (grid)

WorldClim Method: Hijmans et al. 2005

Page 24: Beginner’s GIS

Gridded Climate Models are not just for climatologists any more…

Page 25: Beginner’s GIS

Prism vs. Worldclim

Page 26: Beginner’s GIS

Prism vs. Worldclim

Page 27: Beginner’s GIS

Raster data - remote sensing

Raster Data

Page 28: Beginner’s GIS

Raster data - remote sensing

Ned Horning, Center for Biodiversity and Conservation, AMNH

Raster Data

Page 29: Beginner’s GIS

Raster data - remote sensing

Passive:

Natural EM radiation

e.g. Infrared,Aerial light

photography

Active:

Sensor EM radiation

e.g. RADAR,LIDAR

Raster Data

Page 30: Beginner’s GIS

Common formats:•ESRI ASCII (.asc)•ESRI Grid•Geotiffs (.tif)•Any raster file can be used as a GIS grid

Also:•MrSID•netCDF•BIL

Raster Data

Page 31: Beginner’s GIS

Raster Data

What’s in an ESRI grid?•dblbnd.adf•hdr.adf•sta.adf•vat.adf•w001001.adf –>

actual raster data

•w001001x.adf•prj.adf (opt)

Page 32: Beginner’s GIS

Vector v. Raster

Tradeoffs between the 2 types of data

Page 33: Beginner’s GIS

Tradeoffs between the 2 types of data

Vector v. Raster

Page 34: Beginner’s GIS

Software

Page 35: Beginner’s GIS

GIS software Win Mac GNU/ Linux Unix Web

CARIS Y N Y Y Y

Chameleon Y Y Y Y Y

ERDAS IMAGINE Y N N Y N

ESRI ArcGIS Y N Y Y Y

DIVA-GIS Y Winebottler N N N

GeoServer Y Y Y Y Java

GeoTools Java Java Java Java N

GRASS Y Y Y Y via pyWPS

IDRISI Y N N N N

ILWIS Y N N N N

JUMP GIS Java Java Java Java N

LandSerf Java Java Java Java N

Manifold System Y N N N Y

MapInfo Y N Y Y Y

MapServer Y Y Y Y Y

Maptitude Y N N N Y

Oracle Spatial Y Y Y Y Y

PostGIS Y Y Y Y Y

Quantum GIS Y Y Y Y Y

Smallworld Y ? Y Y Y

SPRING Y N Y Solaris N

TatukGIS Y N N N ?

TransCAD Y N N N Y

TerraView Y N Y N N

TNTmips Y Y Y Y N

TransModeler Y N N N N

Page 36: Beginner’s GIS

ArcGIS• Commercial software, but ESRI Conservation Program grants

support non-profits with free licenses• ArcGIS is a suite of applications: ArcMap, ArcCatalog, ArcTools• Lots of extensions and interacts well with python and R stats with an

extension• Includes, web server, web services, online GIS, and freeware

(ArcExplorer)

Page 37: Beginner’s GIS

DIVA-GIS• Free, not open source• Designed for niche modeling: Bioclim, Domain

Page 38: Beginner’s GIS

uantum GIS• Open source,

• Functionality from plugins in C+ or python

• Access to GRASS and R routines

Page 39: Beginner’s GIS

Some GIS Software Resources• DIVA-GIS

– http://www.diva-gis.org/

• Quantum GIS– http://qgis.org/

• Free Geography Tools – http://freegeographytools.com/

• GISLounge– http://gislounge.com/

• FreeGIS.org– http://freegis.org/

Page 40: Beginner’s GIS

Some GIS Data Resources• Climate Data:

– http://www.worldclim.org/– http://www.prism.oregonstate.edu

• Global Land Cover Facility– http://www.landcover.org/

• EarthExplorer (US DEM, LC) – http://edcsns17.cr.usgs.gov/NewEarthExplorer/

• USGS Seamless Viewer– http://seamless.usgs.gov/

• Global Administrative Boundaries– http://www.gadm.org

Page 41: Beginner’s GIS

Pearson and Dawson 2003 Global Ecology and Biogeography

Scale / Environmental Variable Dependencies