during or just after the time of the year the sun is highest in the sky. There are some
notable exceptions in the middle latitude caused by the presence of summertime
subtropical highs. Finally, there is a land/sea geography to seasonality. Locations
within continents tend to have much greater seasonal temperature and precipitation
swings than do oceanic locations.
Sector Model
A model of hypothetical urban morphology proposed by Homer Hoyt in 1939. The
Hoyt model, as it is sometimes called, was a revision of the Burgess Concentric
Ring model that had been developed in 1925 by the sociologist Ernest Burgess
of the so-called “Chicago School.” Hoytsaw little evidence that cities evolve
and grow in the form of rings around a central zone, and instead offered a schema
that divided the typical city into sections clustered around a central business
district. The sectors were differentiated on the basis of the fundamental economic
activity each would be expected to contain along with the residential characteris-
tics, if any, found there. The model is theoretical and thus does not match any real
city perfectly but offers a generalized explanation of the urban structure. Hoyt’s
model places much more emphasis on the role of transportation in developing
the land-use pattern in urban areas than the Burgess model. He conceived of the
city’s expansion following the lines of transportation, primarily railroads and
street car routes, and this resulted in a more linear pattern of development, result-
ing in blocks of similar spatial functionality, rather than the circular bands of the
Burgess model.
In the Hoyt model, the Central Business District, or CBD, lies at the heart of the
city (see diagram on page 111). It is characterized by high land values, resulting in
tall buildings and congested development. The transportation lines that service the
metropolitan region all converge on the CBD, and thus in the Hoyt model most of
the sectors of development adjoin the CBD to some extent. Adjacent to the CBD
is an area of degenerated industrial production and residences where the unemploy-
ment rate in the city is typically at its highest. This is identified as sector “B1” in the
model and represents the old industrial core of the city. This is a sector in need of
urban renewal, and in many contemporary cities would be experiencinggentrifica-
tion, although Hoyt did not use this term in relation to his model. Located on either
side of the old industrial sector are sectors of poor-quality housing, usually of
tenement-style apartment buildings with little open space. These sectors are
labeled “B2.” Sector “C’ in the model represents middle-class housing, which
according to the Hoyt model is constructed on estates of various sizes. Sector “D”
Sector Model 301