global warming
As of 2020, global mean surface temperature has risen 1°C over the pre-industrial average and is on its way towards 1.5°C. [1]
Even with drastic emission-cutting measures in Europe and North America, world industrial inertia means that warming will most likely not stop at 1.5°C. [2]
Dessler, Andrew E., and Edward A. Parson. The Science and Politics of Global Climate Change: A Guide to the Debate. 3rd ed., Cambridge University Press, 2019.
Current emissions pledges place the world on track for 2.6 - 3.1°C by 2100. [206]
The vast majority of emissions are going to come from undeveloped and rapidly industrializing countries, mostly in Asia and Africa in the future. [204] [205]
Every climate summit has missed its emissions targets. [3]
"Over all, 1,600 coal plants are planned or under construction in 62 countries… The new plants would expand the world’s coal-fired power capacity by 43 percent.
The fleet of new coal plants would make it virtually impossible to meet the goals set in the Paris climate accord, which aims to keep the increase in global temperatures from preindustrial levels below 3.6 degrees Fahrenheit." [207]
Even if the Green New Deal was implemented and successfully reduced the emissions of the United States and the EU to zero by 2030, the effect on global emissions would be only temporary. Emissions from the rest of the world would continue to rise unless also similarly constrained by stringent emissions targets. [204]
The majority of the heat is taken-up by the oceans. Marine heat blobs are becoming more severe as the planet warms. [4]
Sea surface temperature anomaly for the North East Pacific. Dark outlines indicate regions which qualify as marine heatwaves, in terms of their intensity (intensity is a measure of how "anomalously" warm the water is). [85]
Heatwaves as hot as the Sahara are predicted to sweep the planet, the beginnings of which is already occurring. [57] [58]
Inner Asia is experiencing the beginnings of a dramatic shift towards a warmer and drier climate unseen in the region for at least 250 years, according to tree ring data. The loss of soil moisture is driving a positive feedback loop that creates more heatwaves which further dries the soil. [70]
Fires in all regions of California are burning more land area every year. [88]
Seasonal and annual burned areas in California for 1972–2018. (a) Total burned area in the four regions of focus: North Coast, Sierra Nevada, Central Coast, and South Coast. Annual burned area is decomposed into that which occurred in January–April (green), May–September (red), and October–December (orange). Significant (p < 0.05) trends are shown as bold black curves. [88]
Vapor-pressure deficit (VPD) and daily max temperature (Tmax) have been shown to have a positive correlation with area burned.
Standardized precipitation index (SPI), wet day frequency, and dead fuel moisture (FM1000) have negative correlations with burned area. [88]
Correlation between summer (May–September) burned area and climate: 1972–2018. Maps: Regional correlations between the logarithm of summer burned area and mean seasonal climate (outline around region: p < 0.05). Scatterplots represent the full study domain. Climate variables in (a–f): vapor‐pressure deficit (VPD), daily maximum temperature (Tmax), standardized precipitation index (SPI), Wet Day Frequency (frequency of days with precipitation total ≥2.54 mm), 1,000‐hr dead fuel moisture (FM1000), and SPI from March of 2 years prior to the fire year through October of the year prior to the fire year (Antecedent SPI). Colors in scatter plots correspond to the legend in (a). [88]