Revisiting the Geographic Convention of Up and Down: Navigating the Equator and Hemispheres
When we look at a map, we often assume that north is up and south is down. However, this convention raises an interesting question: If north is not really up and south is not down, then why do we say 'above the equator' and 'below the equator'? This means that there is an 'above' and a 'below'. To unravel this complexity, let us explore the concepts of geographical conventions, the equator as a reference point, and the cultural and historical context.
Geographical Convention
The Earth is often depicted in a two-dimensional format on maps where the North Pole is at the top and the South Pole at the bottom. This convention leads to the usage of the equator as a reference point. The equator is an imaginary line that divides the Earth into two hemispheres. It serves as a natural reference point for latitude, with locations north of the equator having positive latitude values and those south of it having negative values. This helps in navigation and understanding global geography.
The Equator as a Reference Point
The equator is crucial in defining the latitude of any location. Latitude measures the north-south position of a point on the Earth's surface and ranges from 0° at the equator to 90° north (North Pole) and 90° south (South Pole). Points to the north of the equator are referred to as north latitude (N), while those to the south are referred to as south latitude (S). This system allows us to specify a point precisely on the Earth's surface using a combination of latitude and longitude, facilitating navigation and global understanding.
Cultural and Historical Context
The orientation of maps with north at the top has historical roots influenced by Western cartography. This convention has become so ingrained that it is almost universal, leading to a common understanding of directionality. However, it is not the only way to orient a map. For instance, if you see the title map of the TV series Bonanza, the top is actually east. The decision to select north is, to a large extent, arbitrary and based on historical and practical reasons.
No Absolute Up or Down
Why did north get priority? One reason might be the presence of the North Star (Polaris) in the Northern Hemisphere, which facilitated navigation by sailors and early explorers. Conversely, the absence of an equivalent in the Southern Hemisphere may have contributed to the prevalence of the north at the top of maps. However, the selection of north is not absolute and is more a matter of convention. Other cultures and maps have different orientations, reflecting the arbitrary nature of direction on a global scale.
Arbitrary Convention
The decision to place north at the top of maps is mostly but not completely arbitrary. It reflects the influence of certain cultural and historical factors, particularly the development of navigation and map-making in the Northern Hemisphere. Anyone who has properly learned map and compass skills knows that this convention is convenient but not absolute. For instance, flat-earthers might use different conventions based on their understanding of the Earth's shape and orientation.
Limitations of Conventions
Maps and globes, especially when using the Mercator projection, can also exhibit projection errors. These errors become significant as one moves closer to the poles. For example, Mercator projection exaggerates the size of landmasses near the poles, which can lead to distortions in political boundaries like those of Colorado (CO) and Wyoming (WY). These controversies illustrate the limitations of these conventions and the need for more accurate projection methods in certain contexts.
Conclusion
While the convention of placing north at the top of maps has become standard due to historical and cultural reasons, it is important to recognize that these conventions are not absolute. Maps serve as tools for navigation and understanding the Earth's geography, but they also come with their limitations. By exploring the equator as a reference point, we gain a deeper understanding of the complexities involved in representing the three-dimensional Earth on a two-dimensional medium.
To fully appreciate the intricacies of geographic conventions, it is essential to study maps and globes closely. Whether you are a cartographer, a navigator, or simply someone interested in understanding our planet, familiarizing yourself with these conventions can enhance your spatial awareness and provide valuable insights into the world around us.