[Moose Test]

There's no way to clear the warning light other than to repair the fault. Whilst there are certainly one or more DTCs being logged, the indicator lamp isn't telling you that, it's telling you that a fault has been detected on this latest power up and self-diagnostic cycle. Therefore if it keeps coming on, then the fault persists.

Standard Volvo mantra applies - read the codes, preferably with VIDA, they will guide you to the fix. That said, given the circumstances, there's no harm in conducting a visual inspection to make sure that all your wheel sensors and their wiring are in place and intact. Also possible that something in the chain has taken on water, again, given the circumstances. So you could check the sensor connections and the state of the connections to the BCM itself for damp ingress. If the light is off when you start the car but comes on shortly into driving it, you can suspect a break in one of the ABS reluctor rings too.

DTC read is likely the quickest route to finding the exact problem, so it depends on how much you value your time, vs having a Volvo dealer or specialist read it for you. A VIDA/DICE setup is relatively cheap and easy to acquire, and likely to pay for itself quickly, so something else to consider if you feel DIY proficient.