Donald Trump angered climate activists again on Thursday with a tweet which appeared to suggest global warming was a positive thing.

His tweet was met with outrage by many, who said he was confusing weather with climate to make his followers doubt climate change.

Climate specialists responded to his tweet forcefully, using data and evidence to disprove his comments. Here’s what they had to say.

Warmer isn’t always better

Canadian climate scientist Katharine Hayhoe had some things to say about the idea that warming up the world a little would be no bad thing.

She posted a video which forms part of a series called Global Weirding. The series aims to answer some basic questions about climate change to help non-scientists understand the impact it it having.

According to Hayhoe, studies have found that anger and bad temper are associated with warmer temperatures and well as a host of other side effects.

Global warming isn’t disproved by cold weather in some areas

As professor of Earth and space sciences and co-founder of the Climate Science Rapid Response Team Scott Mandia reminds us – just because we aren’t experiencing blazing heat right now, it doesn’t mean the world isn’t warming.

In fact, according to the UN’s climate change division, 2017 is set to be one of the three hottest years on record globally, despite the recent dump of snow in some regions.

Climate scientist Michael Mann expanded on this point, sharing data from Climate Signals showing that over the past year in the USA there have been three times as many high temperature records broken as low ones.

Global warming can bring heavier rainfall and more severe storms in some areas of the world while causing drought in other areas.

Who pays for the Paris Accords

The part of Trump’s tweet getting the least notice is his declaration that the US, not any other signatories of the Paris Accord, would have footed a bill for trillions of dollars to pay for it.

As watershed hydrology professor at Kent State University Anne Jefferson comments, each of the 197 signatories of the Paris Agreement came up with their own commitments (termed nationally determined contributions) and signed the agreement voluntarily.

The world needs better language to talk about climate change.

Doug McNeall, climate scientist and statistician at the Met Office, used Trump’s tweet to illustrate the argument that scientists need to find more relatable language to talk about the effects of global warming on the present and future.

Weather and climate are not the same thing

TV meteorologist John Morales used his weather broadcast on NBC 6 to give an overview of the world’s temperatures and set the cold snap in the east USA in context.

The difference between weather and climate is basically time. As NASA puts it: “Weather is what conditions of the atmosphere are over a short period of time, and climate is how the atmosphere ‘behaves’ over relatively long periods of time.”

Global warming is a symptom of the climate changing over a long period of time due to human activity like burning fossil fuels, which releases carbon dioxide into the atmosphere.

As global warming is something that happens over a long period of time, it’s impossible to ask for it to come and warm you up on the east coast of the USA.

The University of Exeter chose to respond to Trump’s tweet offering a free four-week course on their Climate Change: The Science course. Anyone can join, so if you’d like to know more, take a look.