The ocean, and all of the water in it, is constantly in motion. Though it may sometimes appear calm on the surface, enormous currents continuously move ocean water around the globe like a giant conveyor belt. These currents regulate weather, move nutrients across ecosystems, and shape the climates of entire continents. Currents on the surface of the ocean are controlled by the wind, but deeper in the ocean currents are controlled by water density in a process known as thermohaline circulation . Thermohaline refers to the temperature (thermo) and salinity, or saltiness, (haline) of the water. Circulation refers to how the water moves throughout the ocean from pole to pole. Though this is a complicated sounding word, the process is actually pretty simple. Here’s how it works: As ocean water travels toward the poles it becomes colder, and when it gets cold enough, it eventually begins to freeze and forms into sea ice. What is important about this process is that when seawater freezes, the salt is left behind in the surrounding water. As a result, the surrounding water becomes saltier, colder, and in turn becomes more dense than the water around it. Eventually, this water becomes dense enough to sink deep into the ocean, and warmer surface water moves in to replace it. This process of freezing, melting, and replacement continues on and on, resulting in a continuous cycle of moving water that forms deep ocean currents, often referred to as the “global ocean conveyor belt.”

Experts are warning that 2026 may bring a record wildfire season to the United States, so severe that many researchers and fire agencies are no longer calling it a “fire season” at all. We are off to such a start that experts are now referring to it as a fire year. Traditionally, the wildfire season in the United States peaks between May and October, but we have seen many fires throughout the southern and western United States already this spring. Most major fires occur in western states. However, impacts from wildfires can be felt across the entire country, including here in northern Illinois. Wildfire smoke can travel hundreds or even thousands of miles, affecting our air quality here in Rockford. Maybe you recall the hazy skies and dangerous air quality alerts from the last few summers caused by fires burning far away in Canada. Unfortunately, these days are not going away, and if anything, we should expect more of them in the future. So why is this year a “fire year”, and why are experts concerned? Let’s dig into it.