Weather reflects short-term conditions of the atmosphere while climate is the average daily weather for an extended period of time at a certain location. We hear about weather and climate all of the time. Most of us check the local weather forecast to plan our days. And climate change is certainly a "hot" topic in the news. There is, however, still a lot of confusion over the difference between the two.

Think about it this way: Climate is what you expect, weather is what you get.

Weather is what you see outside on any particular day. So, for example, it may be 75 degrees and sunny or it could be 20 degrees with heavy snow. That's the weather.

Climate is the average of that weather. For example, you can expect snow in the Northeast in January or for it to be hot and humid in the Southeast in July. This is climate. The climate record also includes extreme values such as record high temperatures or record amounts of rainfall. If you've ever heard your local weather person say "today we hit a record high for this day," she is talking about climate records.

So when we are talking about climate change, we are talking about changes in long-term averages of daily weather. In most places, weather can change from minute-to-minute, hour-to-hour, day-to-day, and season-to-season. Climate, however, is the average of weather over time and space.

For more information:
National Weather Service

NOAA Climate Services Portal

Coastal Climate Adaptation Resources

Diving Deeper: Preparing for Climate-Related Impacts

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Hurricanes, cyclones, and typhoons are all the same weather phenomenon; we just use different names for these storms in different places. In the Atlantic and Northeast Pacific, the term “hurricane” is used. The same type of disturbance in the Northwest Pacific is called a “typhoon” and “cyclones” occur in the South Pacific and Indian Ocean.

The ingredients for these storms include a pre-existing weather disturbance, warm tropical oceans, moisture, and relatively light winds. If the right conditions persist long enough, they can combine to produce the violent winds, incredible waves, torrential rains, and floods we associate with this phenomenon.

In the Atlantic, hurricane season officially runs June 1 to November 30. However, while 97 percent of tropical activity occurs during this time period, there is nothing magical in these dates, and hurricanes have occurred outside of these six months.

For more information:
Hurricane Basics, National Hurricane Center
What is a hurricane, typhoon, or tropical cyclone? Atlantic Oceanographic and Meteorological Laboratory
Hurricane Season Begins, Making Waves [audio podcast]

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Most people are surprised to learn that, just as the surface of the Earth is not flat, the surface of the ocean is not flat, and that the surface of the sea changes at different rates around the globe. For instance, the absolute water level height is higher along the West Coast of the United States than the East Coast.

You may have heard the term “global sea level,” which refers to the average height of all of the Earth’s ocean basins. “Global sea level rise” refers to the increase in the average global sea level trend.

“Local sea level” refers to the height of the water measured along the coast relative to a specific point on land. Tide stations measure local sea level. “Relative sea level trends” reflect changes in local sea level over time. This relative change is the one most critical for many coastal applications, including coastal mapping, marine boundary delineation, coastal zone management, coastal engineering, sustainable habitat restoration design, and the general public enjoying their favorite beach.

For more information:
Sea Levels Online, Center for Operational Oceanographic Products and Services


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Many people are interested in climate change and how a changing climate will affect the ocean. With the majority of Americans living in coastal states, rising water levels can have potentially large impacts. Scientists have determined that global sea level has been steadily rising since 1900 at a rate of at least 1 to 2.5 millimeters (0.04 to 0.1 inches) per year.

Sea level can rise by two different mechanisms with respect to climate change. First, as the oceans warm due to an increasing global temperature, seawater expands—taking up more space in the ocean basin and causing a rise in water level. The second mechanism is the melting of ice over land, which then adds water to the ocean. The Intergovernmental Panel on Climate Change predicts that total global-average sea level rise from 1990 - 2100 will be 110 to 770 millimeters (4.3 to 30.3 inches).

For more information:
Sea Levels Online, Center for Operational Oceanographic Products and Services
Sea Level Rise, NOAA Science On a Sphere

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The ocean plays an important role in shaping our climate and weather patterns.

Warm ocean waters provide the energy to fuel storm systems that provide fresh water vital to all living things. Understanding and predicting precipitation is critical to farmers who decide which crops to plant, and how deep, based in part on soil moisture levels. Crop and food prices may increase when weather that is too wet or too dry adversely affects crops.

Like precipitation, extreme heat and cold also affect livestock management.

Weather prediction can be a life-saving tool. Aside from helping people prepare for catastrophic storms, prediction can help citizens and governments anticipate extreme hot and cold temperatures, which may cause death among the elderly.

Water management experts study how much rainfall to anticipate so they can manage reservoir levels and water usage, to ensure everyone has abundant water supplies.

For more information:
National Weather Service
NOAA's Climate Prediction Center
The History of Numerical Weather Prediction , NOAA 200th Anniversary Web Site

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