GEOG assignment

Question1:

For the Mercator projection, the area is strongly distorted. For instance, the land area of Greenland and Africa is largely out of proportion.

For the Gall-Peters projection, the shapes of countries may seem to be squished and some countries might appear to be stretched. In this way, the size of areas shown on the map is accurate relative to the physical landmasses.

Question4:

I would like to choose Gall-Peters projection for the first one. Owing to the fact that I need to compare the acreage for agriculture in the United States versus Australia, I need a thematic map and the property that needs to be preserved will be equal area.

Mercator projection is the best choice for marine and air navigation. Under this condition, the shape and angle shown in the map will be extremely important for the captain or pilot. Therefore, the property needs to be preserved is the shape and angle, so I choose Mercator projection.

For the last one, I would like to choose Robinson’s projection, mentioned in the reading materials. This kind of map is called compromise map, which maintains a balance between different properties and avoids extreme distortions. So it will be suitable for a reference map of the world.

Example#2

Question1:

Compare and contrast the Mercator and Gall-Peters projections. Give examples of specific features in each of the maps that have been distorted.

The Mercator projection is conformal, which means that it preserves the shapes and angles of areas on the map. However, this projection can not show the true size of such areas. For example, in reality the size of Greenland is much smaller than Africa, but from the map they appear to be the same size. On the other hand, the Gall-Peters projection is equal area, which preserves the true size of the shapes relative to each other. But at the same time, the shapes and angles are distorted. For example, in order to preserve the area, Greenland now looks like a cluster of dots and lines, which makes it difficult to see what the actual shape of it might be.

Example#3

Question1: In the Mercator projection we see the meridians and parallels intersecting at right angles which preserve the projections shape the area is distorted and uses for this map would be navigation topographic. In the Gail-Peters projection it is for the most part opposite the area is true but the angle and shape are distorted this projection has a thematic use.

Example#4

Question1:

4. For the following scenarios, choose a projection and explain why it would be appropriate.

A. Comparing acreage used for agriculture in the United States versus Australia 

I would suggest using Gall-Peters because land area is preserved.

B. Marine and/or air navigation 

I would suggest Azimuthal Equidistant Projection because distance is preserved which is key in navigation.

C. A reference map of the world

I would suggest mercator because the shape is preserved.

Example#5

Question4:

A. For comparing purely acreage, the Gall-Peters projection would be a good choice because it retains the spatial accuracy of landmasses. It does distort their image, but since this map would not be used for navigation, it does not necessarily need to accurately depict the image/shape of the contents of the map.

B. For long-distance navigational purposes, the retention of both the image of the map and land area may be important, and the only way to preserve both in a practical way is to strategically “slice” the map in certain areas. For this reason, a good choice may be the Interrupted Homolographic. The tradeoff of the lack of a continuous surface is worth the benefits.

C. For a simple reference map, retaining an undistorted image on a continuous surface is the most important feature, thus the best choice in this case would be the Mercator. An argument can be made for the Gall-Peters, but it sacrifices visibility and visual clarity, especially near the poles, which more important than retaining the area of landmasses.

Example#6

Question1:

The Mercator Projection suggests that there is a light source in the center of the earth, projecting the world onto the surface area of a cylinder. However, this method results in the fact that the parts that close to the poles are seriously distorted, the Greenland has the approximated size to the Africa. The Gall-Peters Projection make the map be true for the whole. But the projection also have some distortion. The the parts near the poles are squished(such as Greenland) and the regions near the equator are sort of stretched.

Question2:

A. When comparing acreage used for agriculture in the United States versus Australia, I think we'd better choose the Gall-Peters Projection. Although the shape of countries may be distort, the real size doesn't change. Hence, it is accurate to compared the actual acreages of the two countries.

B. As is widely acknowledged, Modern marine and air navigation also refer to the using of Mercator Projection. When traveling in the sea or air, operators do not necessarily care for the shape of one region. what they actually care for is the veracity of the line. Since the rhumb lines are clearly noted on the map. So the Mercator Projection can be the best choice.

C. I think Robinson Projection can play a role of the reference map of the world. Robinson Projection avoids the extreme distortion and each shape of country closes to the real size. In a word, it can provide people with a comfortable visual effect.

Example#7

Question1:

For the Mercator projection, the countries near the poles are strongly distorted. For instance, Greenland area is much smaller in real life however it appears just as big as Africa. Antarctica is also being exaggerated while Asia and North America seem too small.

For the Gall-Peters projection, the shape of the countries appear to be squished or stretched compared to what they look on the globe. However, by distorting the shape, it preserves the areas and landmasses.

Question4:

For comparing acreage used for agriculture in the United States versus Australia, I think the Gall-Peters projection is the most appropriate choice. Since the map preserves area, it will be a perfect use for assessing land area used for agriculture between countries.

For marine/and or air navigation, I think the Azimuthal Equidistant projection is the most appropriate choice. Since the map preserves distance, it will be perfect for visualizing airplane or marine paths going from one city to another. 

For a reference map of the world, I think the Robinson projection is the most appropriate choice. Since the map keeps a balance between area, distance, and shape without any significant distortion, it'll be a great use for visualizing countries, their areas, and distances around the world.

Example#8

Question1:

Compare and contrast the Mercator and Gall-Peters projections. Give examples of specific features in each of the maps that have been distorted.

The Mercator projection distorts the size of many continents in comparison to one another making Antarctica look bigger than it actually is. The galls-peters projections still distort shape of continents but it preserves the continents areas.  Seeing that Africa is larger in the peter galls shows its accuracy of comparing sizes of continents to one another.

Question4:

For the following scenarios, choose a projection and explain why it would be appropriate.

A. Comparing acreage used for agriculture in the United States versus Australia.

I would use a peter galls because acres concern accurate measures of an area which the peter galls projection preserves.

B. Marine and/or air navigation

For marine and air navigation i would consider using some sort of conic projection to have the result be similar to the perspective of a distance pole.  The Lambert conformal conic might be used although it distorts area but angles and navigation might be similar.

C. A reference map of the world

For a reference map of the world I would use the Mercator because the rhumb lines converse angles and distances from one place to another even though the areas are distorted.