And in Lake Placid, one of the classic harbingers of its arrival is a chair falling through the ice. For decades, the community has had some fun guessing exactly when the ice will melt, or at least become thin enough for a wooden chair to break through.

On top of the fun, the guessing is for a good cause. The annual Ice Out benefit raises money for the Lake Placid Volunteer Ambulance Service. Tickets cost $5, with each one giving the purchaser two guesses, one for Mirror Lake and the other for Lake Placid.

Guesses are down to the minute, and those with the three closest times for each lake will win prizes. People can buy as many tickets as they would like, and they are available for sale at several local businesses and organizations. The full list is below.

¯ Big Z’s at Lake Placid Lanes — 2750 Main St.

From left, teacher Sam Baker and student Kahlen Stevens are seen on Mirror Lake for a science class trip to measure the lake’s ice depth on Tuesday, Jan. 6.

¯ Central Garage — 2679 Main St.

¯ Lake Placid Volunteer Ambulance Service — 388 Mill Pond Dr.

¯ Station Street Wine & Liquor — 6109 Sentinel Road

¯ Terry Robards Wine & Spirits — 2047 Saranac Ave.

¯ The American Legion Post 326 — 2710 Main St.

Lake Placid High School science students, with their teacher Sam Baker, fourth from left, and Paul Smiths College Natural Science Professor Curt Stager, second from right, conduct ice measurements on Mirror Lake on Tuesday, Jan. 6. (Provided photo)

¯ The Bookstore Plus — 2491 Main St.

¯ Wise Guys — 11 School St.

¯ Wyatt’s Tex Mex — 2525 Main St.

Payment and guesses, along with the person’s name and contact information, can also be submitted over the Venmo app to @lpvas46.

“It’s a very unique tradition to Lake Placid,” Lake Placid High School science teacher Sam Baker said. “There’s only a handful of places in the United States that do anything similar to this.”

Much of the fundraiser’s legwork, as in numerous past years, is being carried out by LPHS science students. The class, in addition to setting the chair on Mirror Lake and measuring the lake’s ice depth throughout the winter, has been learning about climate, its changes and the important role that long ice records, such as Mirror Lake’s, play in that analysis.

“We turn when the ice is going to melt underneath the chair into a fun game,” said LPHS ninth grader Bailey Johnson. “The winner gets a cash prize. We raise money and give it to the ambulance service.”

Mirror Lake has one of the longest ice records in the state, stretching back to 1903. It’s not totally complete, but it’s close. In the 122 years, there have been only 11 years without known ice durations, either because the ice-in, ice-out or both dates weren’t recorded that winter season.

“So these records that our grandparents had been keeping for 100-some-odd years, they didn’t know it at the time, but they’re now really good records of how climate has changed in the Adirondacks,” Baker said.

A long record, he said, is needed to highlight long-term trends. One of the concepts that earth science students are learning is the difference between weather and climate. Ninth grader Ceara Stevens explained that weather is what one sees at any given point when they look out the window — how hot or cold it is, if it’s cloudy, raining or snowing. It’s immediate and changes frequently.

Climate, on the other hand, she explained, is the big picture over time. Baker added that two things can be true at once, even as the climate is warming overall, some weeks or seasons — this winter being an example — could be colder than average.

Climate change isn’t a perfectly straight line, he said. Rather, it zigs and zags as the overall trend line moves along. This is reflected in Mirror Lake’s ice record. The Ausable Freshwater Center maintains these graphs, and they are available at tinyurl.com/amvpvd44.

Baker’s class has been working with Paul Smith’s College Natural Sciences Professor Curt Stager, who joined them for one of their Mirror Lake ice measurement trips. He helped explain some of the evidence of climate change and its effects in the Adirondacks, such as shorter seasonal ice durations and thinner ice.

Stevens said she was surprised by how thick the ice had grown this year and how much effort it took to drill the ice auger through to get the sample.

The chair on Mirror Lake can be seen in the background on the right side of the camera frame on the Lake Placid Public Library’s website at lakeplacidlibrary.org. It’s tethered to a 60-foot rope from shore, so it’s easily retrievable once it falls through.

Tickets must be purchased — and guesses locked in — by April 1. Those with questions can email Baker at sbaker@lakeplacidcsd.net.