Global warming is the greatest environmental threat we face and therefore one of the greatest challenges. The clock can't be stopped, so if immediate action is not taken the situation will be irreversible. Solutions to global warming require widespread action by all countries to try to reverse the main causes of climate change (rising sea levels, rising average temperatures melting of the ice caps). For this, nearly 200 countries agreed to set the maximum global temperature threshold at 1.5 degrees Celsius. The commitment is also to reduce net greenhouse gas emissions to zero across the European Union by 2050.