The report, which defines global warming as an increase in combined surface air and sea surface temperatures averaged over the globe and a 30-year period, expresses warming relative to the 1850-1900 timeframe.
"The reality is that we're very off track from where we need to be", says Rachel Cleetus, policy director for the Climate and Energy Program at the nonprofit Union of Concerned Scientists, who was not involved with the new report.
The IPCC has come out with a special report on global warming that said limiting it to 1.5 degrees Celsius will require rapid, far-reaching and unprecedented changes in all aspects of society.
The report said although warming is projected to be the highest in the Northern Hemisphere under 1.5ºC or 2°C of global warming, regions in the tropics and Southern Hemisphere subtropics that are projected to experience the largest impacts on economic growth.
While much has been said about the need to limit global warming temperatures - what exactly is the difference between 2C and 1.5C and how does it impact the world?
The likelihood of an Arctic Ocean free of sea ice in summer would be once per century with global warming of 1.5 °C, compared with at least once per decade with 2 °C.
"Climate impacts are exponentially more dramatic when we go from 1.5C to 2C", said Henri Waisman, a scientist at the Institute for Sustainable Development and International Relations, and a coordinating lead author of the IPCC report.
Limiting global warming would also give people and ecosystems more room to adapt and remain below relevant risk thresholds, added Pörtner.
The WWF called on the European Union to take urgent action to limit global warming to 1.5ºC, saying in a press release: "Approved by 195 governments, the report underscores the small window of opportunity we have to make immediate, deep and transformational changes - without which the world we know will be irreversibly changed".
The report calls for huge changes in land, energy, industry, buildings, transportation and cities. The scientists concluded that carbon dioxide emissions should be cut 45% by 2030 from 2010 levels then reduced to zero by 2050.
Jones' has continued to harp that insurers must act soon, despite indications in past reports that the real effects of climate change are a ways off. "This report gives policymakers and practitioners the information they need to make decisions that tackle climate change while considering local context and people's needs".
The IPCC is a United Nations body assessing the science related to climate change, which has 195 member states.
The report was prepared under the scientific leadership of all three IPCC working groups. From a climate impacts perspective, half a degree is massive as shown in this excellent visual below from the World Resources Institute on the report.
The report lists how Earth's weather, health and ecosystems would be better off if world leaders could figure out how to limit future human-caused warming to 0.5 degree Celsius (0.9 degree Fahrenheit) between 2030 and 2052, instead of the globally agreed upon goal of 1 degree Celsius (1.8 degrees Fahrenheit).
A landmark United Nations report paints a dire picture of the catastrophic consequences the world will face if immediate action is not taken to limit the global warming to 1.5°C, warning that at 2°C, the world could see 10 cm more global sea level rise, loss of all coral-reefs and worsening food shortages.
"Any credible pathway to meeting the 1.5 degree scenario must focus on emissions rather than fuel", Katie Warrick, interim chief executive officer of the WCA, said after reviewing a draft of the report.