A climate factor is any natural or human-caused condition that shapes the long-term weather patterns of a specific region. These factors include average temperature, precipitation, wind, humidity, and atmospheric pressure, measured over decades rather than days. While weather describes what’s happening outside right now, climate factors define what’s normal for a place over 30 years or more. Several major forces determine why one region is a tropical rainforest and another is a desert, even when they sit at similar distances from the equator.
Latitude: The Single Biggest Factor
Latitude is the most important factor governing a region’s surface temperature. The reason comes down to geometry. Near the equator, sunlight strikes the Earth almost straight on, concentrating energy over a smaller patch of ground and producing intense heating. At higher latitudes, the same beam of sunlight hits at a shallow angle, spreading the same energy across a much larger surface area. The result: tropical regions near the equator stay warm year-round, while polar regions remain cold even during their long summer days.
Earth’s 23.5-degree axial tilt adds another layer. As the planet orbits the Sun, that tilt shifts which hemisphere receives more direct sunlight, creating the seasons. A city at 45° north latitude experiences dramatically different solar angles in January versus July, which is why its winters and summers feel like different worlds. A city near the equator barely notices the shift.
Altitude and Temperature
Even within the same latitude, climbing in elevation changes the climate rapidly. Air cools at roughly 10°C for every kilometer of altitude gained (about 5.5°F per 1,000 feet). This is why snow-capped mountains can exist near the equator, like Mount Kilimanjaro in Tanzania. A city on a high plateau will have a cooler, often drier climate than a coastal city at the same latitude. Altitude affects growing seasons, vegetation, and even the oxygen content of every breath you take.
Ocean Currents and Heat Distribution
Ocean currents act like a global conveyor belt, carrying warm water from the equator toward the poles and cold water back toward the tropics. This redistribution of heat is what keeps much of Earth habitable. Without ocean currents, equatorial regions would be far hotter and polar regions far colder, and a much smaller fraction of land would support life.
The Gulf Stream, for example, pulls warm water from the Gulf of Mexico up along the eastern coast of North America and across to western Europe. This is why London, which sits at the same latitude as parts of northern Canada, has mild winters instead of brutal ones. Conversely, cold currents flowing along certain coasts, like the western coast of South America, keep nearby land cooler and drier than you’d expect for the latitude.
Distance From the Ocean
Water and land respond to sunlight very differently, and this contrast creates one of the most noticeable climate factors: continentality. Water has a much higher heat capacity than soil or rock. During the day, land temperatures can swing by tens of degrees, while water temperature changes by less than half a degree. Solar radiation penetrates several meters into water but only a few centimeters into land. Water also mixes and circulates, distributing heat through a greater volume. And oceans retain that heat longer.
The practical effect is straightforward. Coastal cities enjoy moderate climates, with cooler summers and milder winters. Cities deep in the interior of a continent experience temperature extremes in both directions. San Francisco, sitting on the Pacific coast, rarely drops below freezing or rises above 30°C (86°F). Omaha, Nebraska, at nearly the same latitude but far from the ocean, regularly sees both 38°C (100°F) summers and -18°C (0°F) winters.
Mountain Ranges and Rain Shadows
Mountains force air to rise, and rising air cools. If that air carries moisture, it reaches a point where water vapor condenses into clouds and precipitation. The windward side of a mountain range, the side facing the incoming weather, often gets heavy rain or snow. This process is called orographic lifting.
Once the air crests the mountain and descends on the other side, it has already lost most of its moisture as precipitation. As it sinks, it warms rapidly, roughly 10°C per kilometer of descent. Because it’s now drier, it warms faster on the way down than it cooled on the way up (saturated air only cools at about 6.5°C per kilometer). The result is a rain shadow: the land on the leeward side of the mountains is warmer and significantly drier. This explains why the Cascade Range in the Pacific Northwest creates lush rainforest on its western slopes and near-desert conditions on its eastern side, all within a few dozen miles.
Global Wind Patterns
Earth’s atmosphere organizes itself into three major circulation cells in each hemisphere, and these cells determine where rain falls and where deserts form. Near the equator, warm air rises, creating a band of low pressure, heavy rainfall, and tropical rainforests. That rising air moves toward the poles in the upper atmosphere, then sinks back down around 30° north and south latitude, creating bands of high pressure. High pressure means dry, stable air, which is why an outsized number of the world’s deserts cluster around the 30th parallel: the Sahara, the Arabian Desert, the Sonoran, and Australia’s interior.
Between about 50° and 60° latitude, another zone of low pressure brings frequent storms and higher precipitation, particularly along western coastlines. This explains the wet climates of the British Isles, the Pacific Northwest, and southern Chile. These patterns aren’t random; they’re driven by the predictable physics of how heated air circulates on a spinning planet.
Surface Reflectivity
The color and texture of Earth’s surface determines how much sunlight gets absorbed versus reflected, a property called albedo. Fresh snow and ice reflect most incoming sunlight back into space, keeping those surfaces cold. Dark surfaces like ocean water, asphalt, and dense forest absorb most of that energy as heat. This is why cities with large areas of concrete and blacktop develop “heat islands” that run several degrees warmer than surrounding countryside, and why the melting of polar ice creates a feedback loop: as white ice disappears, darker ocean water absorbs more heat, accelerating further warming.
Vegetation plays a role too. A heavily forested region absorbs significantly more solar energy than a sandy desert at the same latitude, which influences local temperatures, humidity, and even rainfall patterns.
Human Activity as a Climate Factor
Greenhouse gas emissions have become a significant climate factor in their own right. Carbon dioxide is the largest single contributor, adding about 2.33 watts of extra energy per square meter to Earth’s surface, according to NOAA’s 2024 measurements. That accounts for roughly 66% of the total warming effect from long-lived greenhouse gases. Methane is the second largest contributor at about 0.57 watts per square meter, or 16% of the total.
These numbers represent the additional energy trapped in the atmosphere compared to pre-industrial levels. That extra energy doesn’t just raise temperatures. It intensifies evaporation, shifts precipitation patterns, alters ocean currents, and changes the behavior of the atmospheric circulation cells that have governed Earth’s climate zones for millennia. In this way, human activity interacts with every other climate factor on this list, amplifying some and disrupting others.