Spoiler
While on the topic of climate change 1.3 degrees is a pretty big deal and thinking otherwise is frankly dumb.
This largely depends on who you ask. The amount of degrees of change that the climate is sensitive too is measured with a statistic called the Equilibrium Climate Sensitivity. The lower the sensitivity measure, the lower impact AGW will have on the climate as a whole. The IPCC 5th AR has it at between 1.5c and 4.5c - if it's at the lower end, then nothing is really wrong, and if it is at the higher end, then we have problems. Recent analysis of the ECS has it at the low end -
https://journals.ametsoc.org/doi/10.1175/JCLI-D-17-0667.1?utm_source=CCNet+Newsletter&utm_campaign=a24cafd790-EMAIL_CAMPAIGN_2018_04_24&utm_medium=email&utm_term=0_fe4b2f45ef-a24cafd790-20156641& - and over the years it's been within that range:
http://www.nationalpost.com/includes/blogs/2018/06_june/fp0619/index.html This statistic is important because the ECS informs on the correct way in which to model the effects of climate change, and if the ECS is this low, the models that spell disaster are running too hot - a trend that has already been noticed (
https://judithcurry.com/2017/09/26/are-climate-models-overstating-warming/). Climate modelling is a very complicated science, and there are many possible reasons for the discrepancy between observations and models!
Spoiler
This is irresponsible for you to post, Theodin - you (should) know as well as anyone else that catastrophic predictions are supported by scientific bodies like the IPCC and the EPA. I have included many helpful links for you to look over! According to the IPCC we can observe many already felt impacts by climate change:
The IPCC believes that limiting climate change to between 1.5C and 2C is crucial to preventing many issues (water availability, extreme drought, protecting ocean ecosystems, heat related mortality, ozone related mortality, general human health and more).
Their summary can be found here readily available on their website (
https://www.ipcc.ch/sr15/) and to suggest that they do not support "catastrophic predictions" about climate change is misleading
This is the problem with using introductions - they can say whatever they want to say! From page 214 (56 in the pdf) of the IPCC's Observations of Atmosphere and Surface (
https://www.ipcc.ch/site/assets/uploads/2017/09/WG1AR5_Chapter02_FINAL.pdf): "AR4 WGI Chapter 3 (Trenberth et al., 2007) did not assess changes in floods but AR4 WGII concluded that there was not a general global trend in the incidence of floods (Kundzewicz et al., 2007). SREX went further to suggest that there was low agreement and thus low confidence at the global scale regarding changes in the magnitude or frequency of floods or even the sign of changes."
The next section about droughts is fascinating, discussing different ways to analyze the subject: "In summary, the current assessment concludes that there is not enough
evidence at present to suggest more than low confidence in a global-scale observed trend in drought or dryness (lack of rainfall) since the middle of the 20th century, owing to lack of direct observations, geographical inconsistencies in the trends, and dependencies of inferred trends on the index choice. Based on updated studies, AR4 conclusions regarding global increasing trends in drought since the 1970s were probably overstated."
On the next page, there's weather events: "In summary, there is low confidence in observed trends in small-scale severe weather phenomena such as hail and thunderstorms because of historical data inhomogeneities and inadequacies in monitoring systems."
Tropical storms: "In summary, this assessment does not revise the SREX conclusion of low confidence that any reported long-term (centennial) increases in tropical cyclone activity are robust, after accounting for past changes in observing capabilities. More recent assessments indicate that it is unlikely that annual numbers of tropical storms, hurricanes and major hurricanes counts have increased over the past 100 years in the North Atlantic basin."
I trust what the scientists tell me!
The EPA, like the Canadian Ministry of the Environment, have nicely written summaries and yet produce these wonderful, easy to use reports that no one reads on things like air quality:
https://gispub.epa.gov/air/trendsreport/2016/ pollutants and emissions have been falling for years all across your country, and overall health and prosperity has increased during that time. Seems like you guys are doing a great job! (Canadian weather data - bit harder to use this site tho
https://www.weatherstats.ca/)
Spoiler
NASA also states that "So, the Earth's average temperature has increased about 2 degrees Fahrenheit during the 20th century. What's the big deal?
Two degrees may sound like a small amount, but it's an unusual event in our planet's recent history. Earth's climate record, preserved in tree rings, ice cores, and coral reefs, shows that the global average temperature is stable over long periods of time. Furthermore, small changes in temperature correspond to enormous changes in the environment.
This sentence is seemingly filler, but it demonstrates the biggest question in climate science - did Mann et al in 2009 understate the effects of the Medieval Warming Period? From the first IPCC assessment report in 1990
https://www.ipcc.ch/site/assets/uploads/2018/03/ipcc_far_wg_I_full_report.pdf (page 250 in the pdf) the MWP is warmer than warming trends currently - which would make NASA incorrect. Mann's analysis using one specific tree ring data set flattened the MWP and pushed current warming up significantly. There are plenty of questions as to whether Mann was correct or not - the man loves to sue other scientists for defamation for criticizing his work. I'm of the opinion that his graph is incorrect, but a more fair conclusion to draw from this summary of the whole shenanigans (
https://wattsupwiththat.com/2018/04/30/20-years-later-the-hockey-stick-graph-behind-waves-of-climate-alarmism-is-still-in-dispute/) is that historical pictures of climate data are not 100% reliable, and drawing conclusions of absolute certainty from them should be met with healthy skepticism.
Spoiler
The 3 Google definitions of "Catastrophic" are as follows:
"involving or causing sudden great damage or suffering."
"extremely unfortunate or unsuccessful."
"involving a sudden and large-scale alteration in state."
Every single one of these is fulfilled by the effects currently felt and possible implications from the future if climate change is to continute at it's current pace.
If the very worst case scenarios are correct, and if the IPCC's analysis about weather events etc are indeed understated, then we'd have a catastrophe with a definition that you so kindly provided. If all this was the case, however, then it is already too late, and you shouldn't worry about trying to abate it. But like I keep telling Winters, the catastrophic scenarios are at this moment very unlikely, and the actual consequences of possible AGW are still quite unknown -
https://www.forbes.com/sites/michaelshellenberger/2019/12/04/why-climate-alarmism-hurts-us-all/amp/?__twitter_impression=true The more pressing concerns for the human race concern poverty, war, and threats to democracy - which don't require complex physics debates to solve!