Tools for geographic enquiry

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Disciplines of geography, cartography & GIS:

Geography: study of place, space & relationships between ppl & the environment

Cartography: study & practice of making maps

GIS: (geographic information systems), a digital system for capturing, storing & displaying spatial data

What are maps? “A map is a symbolic representation of selected characteristics of a place, usually drawn on a flat surface”. (National geographic website)

Common features of maps:

-       Scale: (i.e. 1:100)

-       Orientation (shown by a north arrow)

-       Symbology (symbols, colours & styles used to highlight features on map)

-       Labels & annotations e.g. highlighting names of towns & roads.

-       Legend/ key: so, users knows what the different symbols & styles mean.

-       Grid/graticule: useful for showing distance & highlighting location at smaller scales

-       Marginalia: is additional info e.g. title, author, map projection info (British national grid) & any other info

Why do we need maps? Part 1

-       Navigation: maps of all format e.g. paper, digital, location-enabled mobile devices/satnav systems

-       Aware of other places

-       To know what is where

-       To visualise spatial relationships & patterns- which wouldn’t be visible without a birds eye view

-       To conduct spatial analysis on geographical data e.g. calculating variables like distance, gradient, aspect & intersection

-       Now days maps are not so big & in form of sheets of paper, but interactive geo-databases 

Why do we need maps? Part 2

Flat earth theory!

-       Flat earthers: the theory behind the flat earth movement is that we exist on a large round disk that is surrounded by a wall of ice

-       There is millennia of scientific, astrological & mathematical research that’s gone against the flat earth theory

In reality:

-       Cartography & mapping originate from Ancient Greeks through mathematical & philosophical studies such as Pythagoras, Eratosthenes, Ptolemy (some early attempts at calculating the earths circumference

-       Moving forward in time, records from old sailors who produced charts mapping the seas for navigation also tells use about development of cartography & mapping science – related to the longitude problem & how to calculate it

The shape of the earth: part 1

-       The earth is not a perfect sphere. It’s a geoid (which accounts for the topographic imperfections on the earth’s surface)

-       The earths major axis is its X axis OR the equator & the Earths minor axis is the Y axis (like the lines used to define global time zones)

-       An ellipse is an arc that extends round one side of the globe, from one point on the surface to another. If you rotate an ellipse about its minor or y axis you create an ellipsoid of rotation (closed loop).

-       Our planet is wider at the equator by about 70,000 ft than at the poles. Due to centrifugal force created by earths constant rotation.

Eratosthenes calculation of

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