IN SHORT: There is plenty of evidence presented by countless scientists that global heating and climate change is destroying species, habitats, industries and, with extreme weather events, lives. Downplaying the climate emergency is dangerous.
"There's no emergency," begins the headline of an interview with "dissident climatologist" Dr Judith Curry published on the independent South African website BizNews in October 2022.
The interview can be seen on the site's YouTube channel.
Curry is a US-based climate scientist who, after joining forces with climate change deniers in around 2005, started publicly doubting the scientific rigour of the Intergovernmental Panel on Climate Change, or IPCC. The IPCC, established by the United Nations, is a group of hundreds of climate scientists who study climate change.
In the interview, Curry claims that the Earth's warming is not dangerous or "a bad thing", and that the impacts of climate change have been overstated "in the interests of a good story or political objectives". The interview has received some attention on Facebook.
Curry's claims that climate change is not "bad" or "dangerous" are misleading, and minimise the already observable effects of global heating.
Effects of climate - not 'weather' - change already here
In the interview, Curry does not deny "the basic facts" of climate change.
She says: "Global temperatures have been warming. Humans emit CO2 into the atmosphere. CO2 has an infrared emission spectra which overall acts to warm the planet."
But she disagrees with the IPCC and other climate science experts on factors such as how much people have influenced this warming, and how bad its effects will be.
Climate Change 2021: The Physical Science Basis is the IPCC's sixth assessment report, known as AR6. It was compiled by hundreds of climate scientists and runs into 2,409 pages.
A section of the report reads: "It is unequivocal that human influence has warmed the atmosphere, ocean and land."
But Curry's BizNews interview focuses on the effects of climate change - that there is "no emergency".
Curry says "the weather" today is "not worse than the 1930s or forties or even the fifties". She adds that the only real danger of climate change is sea level rise, which she says will have little effect because people in coastal regions can "move inland".
This is at odds with climate science in several ways.
First, Curry's repeated references to "weather" are misleading as weather is not the same as climate.
There are countless explanations of the difference between weather and climate. We'll go with the one from Nasa, the US National Aeronautics and Space Administration.
"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," the agency explains.
It adds that weather "consists of the short-term (minutes to months) changes in the atmosphere", while climate "is the average of weather over time and space".
So changes in the weather are not the same as changes to the climate. Evidence of climate change, a long-term trend, has already been observed.
In a recent analysis, Nasa and the US National Oceanic and Atmospheric Administration (NOAA) compared recorded global temperature in the three decades from 1951 to 1980 to the eight years leading up to 2021.
The analysis found that the global average temperature is consistently increasing.
"Collectively, the past eight years have been the warmest since modern recordkeeping began in 1880," reads a report on the analysis, published in January 2022.
Curry claims that the 1970s and 1980s "was a relatively benign period of weather", and that "weather" today is "not worse than the 1930s or forties or even the fifties".
The 1940s were somewhat warmer than the 1951 to 1980 average, but - aside from confusing weather and climate - her claim understates the warming trend observed since.
Global average temperatures have increased by nearly one degree Celsius (the figure was 0.85°C in 2021) since the 1951-to-1980 benchmark. The benchmark is itself noticeably warmer than temperatures in the late 1800s, when records began.
But the evidence for climate change and its effects isn't limited to warming.
It's not just temperature that's changing
The IPCC's AR6 report includes a section titled Impacts, Adaptation and Vulnerability.
It lists impacts of climate change that have already been observed. The full list is too long to repeat here.
But it includes evidence that changes in climate have:
Caused species to die off and habitats to shrink
Reduced the productivity of agriculture and fishing sectors
Increased the frequency of extreme weather events such as heatwaves, droughts, cyclones, and wildfires
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Climate is understood by long-term trends, so single observations - the survival status of a species in a year, or an extreme weather event - can't be used in arguments for or against climate change.
But there is evidence that these events would likely not have happened without the long-term changes in climate caused by human activity.
NOAA explains: "To date, climate research has yet to show that any given event was caused solely by global warming.
"However, over the past decade, research has demonstrated that climate change due to global warming has made many extreme events more likely, more intense, longer-lasting, or larger in scale than they would have been without it."
It quotes a collection of yearly studies by the American Meteorological Society into the links between human-caused climate change and extreme weather events.
Studies such as these, as well as the IPCC assessments, often have some degree of uncertainty in their results. But, as we have explained before, this statistical uncertainty does not invalidate the findings, especially as further studies come to the same conclusions.
The IPCC assessments are based on hundreds of peer-reviewed studies, and while the predictions made by these studies aren't certain to be accurate, they represent the best available evidence for human-caused climate change and its impacts.
