What's the Difference Between Weather and Climate?

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iStock

What do we talk about when we talk about climate? Contrary to what some science coverage would have you believe, it isn't the same thing as the weather. Though the terms are often (and mistakenly) used interchangeably, the difference between weather and climate boils down to time.

One of the easiest ways to describe the difference between weather and climate is to think of the weather as your mood on a certain day, while the climate is your overall personality. You can be in a foul mood today, a great mood tomorrow, and feel blah the day after that, but if you’re chipper and friendly more often than not, then you generally have an agreeable personality, despite the occasional off-day. The relationship between weather and climate works in much the same way.

The weather is what we experience on a short-term basis. Morning fog, afternoon thunderstorms, and a hurricane looming offshore are all examples of weather since they’re taking place in the present. We have lots of specialized weather models that are really good at predicting specific weather events for a period of around seven days into the future. We’re able to predict factors like exact temperatures, rainfall totals, and wind speeds with great accuracy over that short period of time.

Climate, on the other hand, is the overall trend of weather patterns over a long period of time. The temperature can vary wildly from day to day, but if your city usually experiences more warm days than cold days, you live in a warm climate. Just because you live in a warm climate doesn’t mean it’s always going to be warm, of course, but it’s likely going to be warm more often than not.

Scientists also have models that can predict climatic trends over months and even years, but they can’t give us the same specific, granular data points that weather models can suss out. A climate model can’t tell you the exact high temperature three months from today, but we do have the ability to tell you in June if temperatures in August across a certain region are likely to be warmer or cooler than average.

Scientists can use what we know about climate change in the past, the world today, and what evidence tells us the world will look like in the future to give us an idea of how climate trends will change with time. This is how scientists are fairly certain that a warming climate is causing more extreme weather conditions like hotter heat waves and more intense bouts of heavy rain.

That said, climate change isn't happening all at once, but slowly, and will continue to do so over the coming decades. There have always been unpleasant weather events, like heat waves and heavy rains, and for now, there will continue to be. But scientists say we should expect that these weather events will only get more extreme over time.

Storm Leaves Homes Along Lake Erie Covered in Up To Three Feet of Ice

Houses along Lake Erie's shoreline were pummeled with sheets of icy water during a storm last week.
Houses along Lake Erie's shoreline were pummeled with sheets of icy water during a storm last week.
John Normile/Getty Images

This past weekend, lakeside residents of Hamburg, New York, awoke to find their neighborhood transformed into a full-scale replica of Frozen’s ice-covered kingdom, Arendelle.

According to CNN, gale force winds produced giant waves that sprayed the houses along Lake Erie with sheets of water for two days straight, covering them in layers of ice up to three feet thick.

“It looks fake, it looks surreal,” Hamburg resident Ed Mis told CNN. “It’s dark on the inside of my house. It can be a little eerie, a little frightening.”

While the homeowners are anxious for the ice to melt, they’re also concerned about what could happen when it does.

“We’re worried about the integrity, of structure failure when it starts to melt, because of the weight on the roof,” Mis said.

He added that this is the worst ice coating he’s seen since he moved to the area eight years ago—but it’s not because they’ve had a particularly harsh winter. In fact, just the opposite is true. According to The Detroit News, warm winter temperatures have caused ice cover on the Great Lakes to drop from 67 percent in 2019 to less than 20 percent this year.

“Lake Erie typically has significant ice cover by this time of the year, and that protects the shoreline from these battering storms,” The Weather Channel’s winter weather expert Tom Niziol explained in a video.

The phenomenon has created another unforeseen issue for Hamburg’s coast, too: Tourism. The local police department posted a message on Facebook on Sunday, March 1, asking people to keep off both the “extremely unsafe and unstable” ice and people's private property.

[h/t CNN]

What is Lake-Effect Snow?

Tainar/iStock via Getty Images
Tainar/iStock via Getty Images

As you probably guessed, you need a lake to experience lake-effect snow. The primary factor in creating lake-effect snow is a temperature difference between the lake and the air above it. Because water has a high specific heat, it warms and cools much more slowly than the air around it. All summer, the sun heats the lake, which stays warm deep into autumn. When air temperatures dip, we get the necessary temperature difference for lake-effect snow.

As the cool air passes over the lake, moisture from the water evaporates and the air directly above the surface heats up. This warm, wet air rises and condenses, quickly forming heavy clouds. The rate of change in temperature as you move up through the air is known as the "lapse rate"; the greater the lapse rate, the more unstable a system is—and the more prone it is to create weather events.

Encountering the shore only exacerbates the situation. Increased friction causes the wind to slow down and clouds to "pile up" while hills and variable topography push air up even more dramatically, causing more cooling and more condensation.

The other major factors that determine the particulars of a lake-effect snowstorm are the orientation of the wind and the specific lake. Winds blowing along the length of a lake create greater "fetch," the area of water over which the wind blows, and thus more extreme storms like the one currently pummeling the Buffalo area. The constraints of the lake itself create stark boundaries between heavy snow and just a few flurries and literal walls of snow that advance onto the shore. The southern and eastern shores of the Great Lakes are considered "snow belts" because, with winds prevailing from the northwest, these areas tend to get hit the hardest.

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