domingo, 16 de febrero de 2014

Hi everyone! I`m Marta Saura Hernández and I`m the journalist this week.
A part from the presentation, we have to do another two activities related with this topic. Here you can see our work:
First of all, we have to do an activity which consists of fill in the gap with words related to the activity.
We have decided these five words: 

 A ____MAP____ is the only “perfect” representation of the Earth’s surface. All
maps are distorted in four major ways. The four ways maps are distorted is by
the ___SHAPE_____, ____SIZE_____, ____LATITUDE_____, and
___LONGITUDE____ of the landmasses being mapped. In order to make maps,
projections must be made, and different projections require different distortions.
For each projection listed below, complete the chart for the correct information.  

Also you can have a look an interesting webpage about some important aspects of maps and cartographic projections, here you have it:
http://wiki.answers.com/Q/What_are_the_4_ways_in_which_maps_can_be_distorted?#slide=2

The second activity consisted of complete a chart with different information about cartographic projections. 
To complete this chart we had to look for information about the three projections and later on, we focus on this table to answer the big questions.
Here you can see our chart: 


PROJECTION
ROBINSON


PICTURE




PURPOSE

It shows the world as flat. The objective was to express the whole globe easily in a flat image. It makes various aspects of the map slightly distorted to produce an attractive world map.






DISTORTION – TYPES?
The meridians curve gently, avoiding extremes, but thereby stretch the poles into long lines instead of leaving them as points.
The straight parallels imply severe angular distortion at the high latitudes toward the outer edges of the map.
Robinson maps show lines of latitude as parallel straight lines and lines of longitude as nonparallel lines.






DISTORTION – AREAS
THAT ARE MOST
DISTORTED?

This projection tried to stretch the globe, so countries trended to be bigger in the north and south than countries located near equator, which are more close to the real dimension. In this case, Canada is bigger than its dimension on reality. On the contrary, Italy is smaller than its dimension on reality.
THERE IS MORE
THAN ONE VERSION?
The development of the Robinson projection is unique in that it was a response to a request by a map and atlas production company (Rand McNally) to develop a better visual representation of the world for use in its publications.

PROBLEMS?
The projection is not equal or conformal, because Robison thought that the globe would be shown as a whole. The Robinson projection is not equidistant; there is no point or points from which all distances are shown accurately. 


SOCIO-CULTURAL
IMPLICATIONS OF
USING IT AS A
LEARNING
RESOURCE?
It was a response to a request by a map and atlas production company (Rand McNally) to develop a better visual representation of the world for use in its publications. It has also been adopted by the National Geographic Society for use in many of the maps featured in its magazine and map products.


PROJECTION
MERCATOR


PICTURE




PURPOSE

It tried to represent the globe on a cylindrical surface.





DISTORTION – TYPES?
Mercator projection distorts the size and shape of large objects, as the scale increases from the Equator to the poles, where it becomes infinite. The lines of latitude and lines of longitude appear as straight lines running parallel and perpendicular to each other. The distances and areas are greatly distorted in higher latitudes.






DISTORTION – AREAS
THAT ARE MOST
DISTORTED?
The Mercator projection exaggerates areas far from the equator. With this projection, Canada takes as much space on the map as Africa, when in reality Africa is bigger than Canada. Italy takes fewer space than Tasmania Island, because the latter is near south pole.

THERE IS MORE
THAN ONE VERSION?
In 1772 Johann Heinrich Lambert released the Transverse Mercator projection. It is based on the highly successful of Mercator Projection. The main strength of the Mercator projection is that it is highly accurate near the Equator and the main problem with the projection is that distortions increase away from the Equator.  This set of virtues and vices meant that the Mercator projection is highly suitable for mapping places which have an east-west orientation near to the Equator but not suitable for mapping places which have are north-south orientation (eg South America).


PROBLEMS?
Mercator projection doesn`t keep the relationships among areas of different levels of latitude. The Mercator projection is not suited to general reference world maps because of its distortion of land area.


SOCIO-CULTURAL
IMPLICATIONS OF
USING IT AS A
LEARNING
RESOURCE?
Many major online street mapping services (Google Maps) use a variant of the Mercator projection for their map images, despite its obvious scale variation at small scales, the projection is well-suited as an interactive world map. Mercator projection is still the standard for many world nautical charts. It is also still commonly used in many classrooms for large wall maps of the world.



PROJECTION
AZIMUTHAL


PICTURE




PURPOSE
It represents all points on the map at proportionately correct distances from the center point, and that all points on the map are at the correct direction from the center point.






DISTORTION – TYPES?


 Distances and directions to all places are true only from the center point of projection. Areas located in the center point have right dimension whereas areas located far from this point have several distortions in their distances.







DISTORTION – AREAS
THAT ARE MOST
DISTORTED?

In Azimuthal projection we can see that areas, for example Canada, have right or similar dimensions that we have nowadays in our maps because they are near to the center point. If we have a look of an area located in the equator, for example Italy, we can observe that their dimension are distort from the reality.

THERE IS MORE
THAN ONE VERSION?
The oldest known record of this projection is from Ptolemy in about 150 AD.  However it is believed that this projection was well known long before that time – probably as far back as the 2nd century BC.

PROBLEMS?
Distances are correct between points along straight lines through the center. All other distances are incorrect. Distortion of areas and shapes increases with distance from center point. Azimuthal projection is neither equal-area nor conformal.

SOCIO-CULTURAL
IMPLICATIONS OF
USING IT AS A
LEARNING
RESOURCE?
It is most commonly used over Polar areas, but can be used for small scale maps of continents such as Australia.
The advantage of this is that for a place of interest a map which uses the Stereographic projection and is centred on that place of interest true distances, can be calculated to other places of interest.
As I said before, to complete this chart I looked for information in some interesting webpages. Have a look!

We are continuing with the activity, soon we will see our work.

Post made by the journalist: Marta Saura Hernández.

1 comentario:

  1. Problem: there are fragments completely copied from other sites on the Internet without reference... this is plagiarism, and plagiarism will be grade with a 0. SO solve it AND, don't it again,

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