Physical geography, which deals with the physical factors of a region, is a geographical sub-field concerned with the features, processes and patterns that make up the natural environment. Physical geography is typically understood in contrast to human geography, which focuses on the environment as built and modified by humanity.
Physical geography is particularly guided by an interest in the spatial relationships that exist between the Earth's atmosphere, hydrosphere, biosphere and lithosphere; in addition to the natural phenomena that exist within, and interact between, them. Physical geography is equally concerned with features characterizing the surface of the earth, such as specific landforms, mountains, soil, glaciers, rivers and oceans.
Within this broad range of interests, physical geography also tackles a number of pragmatic and deeply fundamental problems. For example, in researching the relationships between the spheres, physical geographers study climate change and its effect on the natural environment. Additionally, some physical geographers choose to chronicle the impact of solar activity on the earth.
In a broader sense, physical geographers are concerned with potential hazards. These include natural disasters caused by storm such as hurricanes, tsunamis and tornadoes, as well as the potentially catastrophic effects of global warming on terrestrial ecosystems. As such, physical geography boasts an extremely diverse set of sub-fields, which include climatology, meteorology, oceanography, landscape ecology, geomorphology, glaciology and hydrology.