“Severe, widespread and irreversible” damage will hit planet earth unless urgent action is taken to cut back on burning fossil fuels in order to limit global warming.
The warning comes from the Intergovernmental Panel on Climate Change, a United Nations body.
Its report says that global warming, caused by greenhouse gas emissions, already has arrived.
People can expect more extreme weather conditions, such as floods, heat waves and droughts.
The report also warns that climate change could even add to the risk of violent conflicts.
The possible “substantial” risks involved in taking costly action are not as great, the report says, than the risks to be faced if climate change continues. The longer action is delayed, the more it will cost.
The UN has previously set a target of limiting global warming to 2C (3.6F) above pre-industrial levels. But the report says it appears increasingly likely that target will be missed, leading to more severe impacts.
The report is the pulling together of the findings of three previous reports into the science and impacts of climate change which the UN body had previously presented.
The final report is due to be released in November following a conference in Copenhagen where governments must agree its wording line-by-line.
Meanwhile, Portugal currently is on yellow alert, the third most serious on a scale of four, with heavy rain forecast and storms across the mainland between 6am and midnight on Thursday, according to the Portuguese weather service.
The Azores will miss the worst of the weather but the Algarve will be affected in the early afternoon and later in the evening.
The general forecasts is for very cloudy skies and rain along the west coast and into the interior with thunder and lightning.
