On Saturday, 195 nations signed an agreement that for the first time commits all nations, rich and poor, to lowering greenhouse gas emissions. The goal is to prevent a rise in temperatures of 2 degrees Celsius or 3.6 degrees Fahrenheit.
The deal represents an important turning point in climate change global policy. It will also be a trigger for climate change skeptics to again begin pointing out events - like blizzards and colder-than-normal weather - that seem like reasons to dispute global warming.
Part of the confusion comes down to our understanding of weather and climate. People question the scientific reality of global warming because they don't know the difference.
Weather is what we see day-to-day. It explains changes in the atmosphere over short periods of time and is highly unpredictable. A sudden thunderstorm or blizzard is what we might refer to as weather.
Climate, on the hand, describes the behavior of the atmosphere over long periods of time.
There will continue to be hot and cold extremes, but when the weather is averaged over time, a clear warming trend emerges. The past decade has been found to be the hottest since scientists started recording data in the 1880s.
So how to do we draw the link between extreme weather events and climate change?
It's virtually impossible to tie any given weather event to global warming or not. But we can say that droughts, heatwaves, hurricanes, and wildfires are happening with more frequency and intensity alongside the warming trend.
British climate scientist Adam Levy, known as Climate Adam on his YouTube channel, explains this well in an experiment using microwave popcorn.
In the experiment, the popcorn kernels represent one year's worth of weather events.
If a corn pops as it's heated up in the microwave, that represents one extreme event.
At first, Levy microwaves the corn on low heat for 30 seconds.
Two kernels pop. That means two weather events turned out to be extreme in the first year:
Climate Adam
To see how global warming changes things, Adam cranks up the heat.
Levy put the kernels in the microwave on high heat for 30 seconds. The extra heat makes seven kernels pop.
Levy explains: "We can't say which particular pops were caused by the extra heat. And which would have popped either way. But we can say that the extra heat made popping more likely."
The same principle can be applied when we talk about a warming planet.
Levy adds: "We can't say that a particular extreme weather event definitely happened because of climate change. But we can say that climate change is making certain extreme weather events happen more often."
Anecdotally, the record rainfall in northern England is some of the most recent evidence to support this phenomenon.
You can watch the full experiment below and check out more videos from Climate Adam here.