The State Similarity Index attempts to quantify how similar states are to each other relative to other states. The index is a statistically-based way to measure this. 20% of the index is based on geography. 10% of a state’s geography score (2% of the overall State Similarity Index score) is based on a state’s geomorphology. This includes the state’s physiographic and hydrologic regions.
Coastline Adjacency
The United States possesses diverse and captivating coastlines that can be categorized into distinct regions. Alaska is the only state that borders the Arctic Ocean. It is characterized by its rugged and pristine beauty, where icy shores meet towering glaciers and unique ecosystems thrive. Along the eastern United States, the Atlantic coastline stretches from Maine to Florida, offering a mix of sandy beaches, rocky cliffs, and historic coastal towns. Although the Great Lakes are not oceans, the states that border them have a lot of freshwater coastline. Moving south, the Gulf of Mexico has a warm and tropical coastline, distinct from the rest of the Atlantic Ocean. Along the western edge of the country, the Pacific coastline showcases dramatic cliffs, sandy beaches, and stunning rock formations. Finally, while the United States has vast coastlines, there are also many landlocked states that lack direct access to the sea.
Source: Wikipedia
Coastline categories:
Arctic, Atlantic, Great Lakes, Gulf of Mexico, Pacific, Landlocked
Drainage Basin
Although many states do not have coastline, most of the water in these states eventually ends up in the ocean. The Gulf of Mexico drainage basin covers the largest portion of the United States, with major rivers like the Mississippi, Missouri, and Rio Grande flowing into the ocean. Still, some water does not flow into the oceans. The Great Basin drainage basin, centered around Nevada and parts of surrounding states, is unique as it lacks an outlet to the sea, with rivers flowing into the Great Salt Lake or evaporating in desert regions. The Great Lakes drainage basin encompasses areas around the Great Lakes, forming a vast freshwater system that includes the St. Lawrence River, which eventually discharges into the Atlantic Ocean.
Source: Wikipedia
Drainage basin categories:
Arctic, Atlantic, Great Basin, Great Lakes, Gulf of Mexico, Hudson Bay, Pacific
Physical Division
The United States exhibits a remarkable diversity of physiographic regions, showcasing the country’s varied landscapes. The Intermontane region, primarily found in the western states, is characterized by vast basins, plateaus, and rugged mountain ranges. The Pacific Mountain division encompasses the coastal mountain ranges stretching from California to Alaska, including the iconic Sierra Nevada and Cascade Range. The Rocky Mountain division, located in the western part of the continent, features majestic peaks, deep valleys, and extensive forests. The Interior division spans the central parts of the country, comprising vast plains, rolling hills, and river valleys, such as the Great Plains and the Mississippi River Valley. The Eastern Highland division comprises the Appalachian Mountains, running from Maine to Alabama, and includes picturesque valleys, rugged peaks, and ancient rock formations.
Source: Library of Congress
Physiographic divisions:
Intermontane, Pacific Mountain, Rocky Mountain, Interior, Eastern Highland
Physical Subdivision
Physiographic divisions can be further divided into smaller subdivisions. For example, the Ozark Mountains are part of the Eastern Highlands region, but this area is further broken up into Appalachian Highlands and Interior Highlands. These smaller subdivisions within the physiographic divisions highlight the diverse geological features and microclimates present within the United States, offering a deeper understanding of the country’s varied landscapes.
Source: Library of Congress
Physiographic subdivisions:
Intermontane Plateaus, Interior Plains, Pacific Mountain, Rocky Mountain, Arctic, Hawaii, Appalachian Highlands, Interior Highlands, Atlantic Plain, Laurentian Upland
