rlacombe/ClimateX huggingface dataset:
New evidence strengthens the conclusion from the IPCC Special Report on Global Warming of 1.5°C (SR1.5) that even relatively small incremental increases in global warming (+0.5°C) cause statistically significant changes in extremes on the global scale and for large regions (IPCC AR6_WGI, confidence: high)
In particular, this is the case for temperature extremes (very likely), the intensification of heavy precipitation (high confidence) including that associated with tropical cyclones (medium confidence), and the worsening of droughts in some regions (IPCC AR6_WGI, confidence: high)
Projected percentage changes in frequency are higher for the rarer extreme events (IPCC AR6_WGI, confidence: high)
There have been improvements in some observation-based datasets, including reanalysis data (IPCC AR6_WGI, confidence: high)
Climate models can reproduce the sign (direction) of changes in temperature extremes observed globally and in most regions, although the magnitude of the trends may differ (IPCC AR6_WGI, confidence: high)
Models are able to capture the large-scale spatial distribution of precipitation extremes over land (IPCC AR6_WGI, confidence: high)
The intensity and frequency of extreme precipitation simulated by Coupled Model Intercomparison Project Phase 6 (CMIP6) models are similar to those simulated by CMIP5 models (IPCC AR6_WGI, confidence: high)
Higher horizontal model resolution improves the spatial representation of some extreme events (e.g., heavy precipitation events), in particular in regions with highly varying topography (IPCC AR6_WGI, confidence: high)
Irrigation and crop expansion have attenuated increases in summer hot extremes in some regions, such as the Midwestern USA (IPCC AR6_WGI, confidence: medium)
In most regions, future changes in the intensity of temperature extremes will very likely be proportional to changes in global warming, and up to two to three times larger (IPCC AR6_WGI, confidence: high)
The highest increase of temperature of hottest days is projected in some mid-latitude and semi-arid regions and in the South American Monsoon region, at about 1.5 times to twice the rate of global warming (IPCC AR6_WGI, confidence: high)
The highest increase of temperature of coldest days is projected in Arctic regions, at about three times the rate of global warming (IPCC AR6_WGI, confidence: high)
Evidence of a human influence on heavy precipitation has emerged in some regions (IPCC AR6_WGI, confidence: high)
At the global scale, the intensification of heavy precipitation will follow the rate of increase in the maximum amount of moisture that the atmosphere can hold as it warms (IPCC AR6_WGI, confidence: high)
The increase in the frequency of heavy precipitation events will be non-linear with more warming and will be higher for rarer events (IPCC AR6_WGI, confidence: high)
Increases in the intensity of extreme precipitation at regional scales will vary, depending on the amount of regional warming, changes in atmospheric circulation and storm dynamics (IPCC AR6_WGI, confidence: high)
The seasonality of river floods has changed in cold regions where snow-melt is involved, with an earlier occurrence of peak streamflow (IPCC AR6_WGI, confidence: high)
Increases in evapotranspiration have been driven by increases in atmospheric evaporative demand induced by increased temperature, decreased relative humidity and increased net radiation (IPCC AR6_WGI, confidence: high)
Trends in precipitation are not a main driver in affecting global-scale trends in drought (IPCC AR6_WGI, confidence: medium)
Regional- scale attribution shows that human-induced climate change has contributed to increased agricultural and ecological droughts (MED, WNA), and increased hydrological drought (MED) in some regions (IPCC AR6_WGI, confidence: medium)
Several regions will be affected by more severe agricultural and ecological droughts even if global warming is stabilised at 2°C, including MED, WSAF, SAM and SSA (high confidence), and ESAF, MDG, EAU, SAU, SCA, CAR, NSA, NES, SWS, WCE, NCA, WNA and CNA (IPCC AR6_WGI, confidence: medium)
At 4°C of global warming, about 50% of all inhabited AR6 regions would be affected by increases in agricultural and ecological droughts (WCE, MED, CAU, EAU, SAU, WCA, EAS, SCA, CAR, NSA, NES, SAM, SWS, SSA, NCA, CNA, ENA, WNA, WSAF , ESAF , MDG: medium confidence or higher), and only two regions (NEAF , SAS) would experience decreases in agricultural and ecological drought (IPCC AR6_WGI, confidence: medium)
Peak TC rain rates increase with local warming at least at the rate 2 Six-hourly intensity estimates during the lifetime of each TC.of mean water vapour increase over oceans (about 7% per 1°C of warming) and in some cases exceeding this rate due to increased low-level moisture convergence caused by increases in TC wind intensity (IPCC AR6_WGI, confidence: medium)
None of these changes can be explained by natural variability alone (IPCC AR6_WGI, confidence: medium)
The total global frequency of TC formation will decrease or remain unchanged with increasing global warming (IPCC AR6_WGI, confidence: medium)
Future wind speed changes are expected to be small, although poleward shifts in the storm tracks could lead to substantial changes in extreme wind speeds in some regions (IPCC AR6_WGI, confidence: medium)
The frequency of spring severe convective storms is projected to increase in the USA, leading to a lengthening of the severe convective storm season (IPCC AR6_WGI, confidence: medium)
Concurrent heatwaves and droughts have become more frequent, and this trend will continue with higher global warming (IPCC AR6_WGI, confidence: high)
Fire weather conditions (compound hot, dry and windy events) have become more probable in some regions (IPCC AR6_WGI, confidence: medium)
The probability of compound flooding (storm surge, extreme rainfall and/or river flow) has increased in some locations (medium confidence), and will continue to increase due to sea level rise and increases in heavy precipitation, including changes in precipitation intensity associated with tropical cyclones (IPCC AR6_WGI, confidence: high)
The land area affected by concurrent extremes has increased (IPCC AR6_WGI, confidence: high)
Compound events, including concurrent extremes, are a factor increasing the probability of low- likelihood, high-impact events (IPCC AR6_WGI, confidence: high)
With increasing global warming, some compound events with low likelihood in past and current climates will become more frequent, and there is a higher chance of occurrence of historically unprecedented events and surprises (IPCC AR6_WGI, confidence: high)
However, even extreme events that do not have a particularly low probability in the present climate (at more than 1°C of global warming) can be perceived as surprises because of the pace of global warming (IPCC AR6_WGI, confidence: high)
Anthropogenic forcing (e.g., increases in greenhouse gas concentrations) directly affects thermodynamic variables, including overall increases in high temperatures and atmospheric evaporative demand, and regional changes in atmospheric moisture, which intensify heatwaves, droughts and heavy precipitation events when they occur (IPCC AR6_WGI, confidence: high)
Land use can affect regional extremes, in particular hot extremes, in several ways (IPCC AR6_WGI, confidence: high)
Aerosol forcing also has a strong regional footprint associated with regional emissions, which affects temperature and precipitation extremes (IPCC AR6_WGI, confidence: high)
These can also lead to a higher warming of extreme temperatures compared to mean temperature (high confidence), and possibly cooling in some regions (IPCC AR6_WGI, confidence: medium)
Phenomenon and Direction of TrendProjected Changes at +1.5ºC Global WarmingProjected Changes at +2°C Global WarmingProjected Changes at +4°C Global Warming Warmer and/or more frequent hot days and nights over most land areas Warmer and/or fewer cold days and nights over most land areas Warm spells/heatwaves; increases in frequency or intensity over most land areas Cold spells/cold waves: decreases in frequency or intensity over most land areasVirtually certain on global scale Extremely likely on all continents Highest increase of temperature of hottest days is projected in some mid-latitude and semi-arid regions, and the South American Monsoon region, at about 1.5 times to twice the rate of global warming (high confidence) {11.3, Figure 11.3} Highest increase of temperature of coldest days is projected in Arctic regions, at about three times the rate of global warming (high confidence) {11.3} Continental-scale projections: Extremely likely : Africa, Asia, Australasia, Central and South America, Europe, North America {11.3, 11.9}Virtually certain on global scale Virtually certain on all continents Highest increase of temperature of hottest days is projected in some mid-latitude and semi-arid regions, and the South American Monsoon region, at about 1.5 times to twice the rate of global warming (high confidence) {11.3, Figure 11.3} Highest increase of temperature of coldest days is projected in Arctic regions, at about three times the rate of global warming (high confidence) {11.3} Continental-scale projections: Virtually certain: Africa, Asia, Australasia, Central and South America, Europe, North America {11.3, 11.9}Virtually certain on global scale Virtually certain on all continents Highest increase of temperature of hottest days is projected in some mid-latitude and semi-arid regions, and the South American Monsoon region, at about 1.5 times to twice the rate of global warming (high confidence) {11.3, Figure 11.3} Highest increase of temperature of coldest days is projected in Arctic regions, at about three times the rate of global warming (high confidence) {11.3} Continental-scale projections: Virtually certain: Africa, Asia, Australasia, Central and South America, Europe, North America {11.3, 11.9} Heavy precipitation events: increase in the frequency, intensity, and/or amount of heavy precipitation High confidence that increases take place in most land regions {11.4} Very likely: Asia, North America Likely: Africa, Europe High confidence: Central and South America Medium confidence: Australasia {11.4, 11.9}Likely that increases take place in most land regions {11.4} Extremely likely: Asia, North America Very likely: Africa, Europe Likely: Australasia, Central and South America {11.4, 11.9}Very likely that increases take place in most land regions {11.4} Virtually certain: Africa, Asia, North America Extremely likely: Central and South America, Europe Very likely Australasia {11.4, 11.9} Agricultural and ecological droughts: increases in intensity and/or duration of drought events More regions affected by increases in agricultural and ecological droughts compared to observed changes (IPCC AR6_WGI, confidence: high)
Compound events, including concurrent extremes, are a factor increasing the probability of LLHI events (IPCC AR6_WGI, confidence: high)
With increasing global warming, some compound events with low likelihood in past and current climate will become more frequent, and there is a higher chance of historically unprecedented events and surprises (IPCC AR6_WGI, confidence: high)
Land–atmosphere feedbacks strongly modulate regional- and local-scale changes in temperature extremes (IPCC AR6_WGI, confidence: high)
Regional external forcings, including land-use changes and emissions of anthropogenic aerosols, play an important role in the changes of temperature extremes in some regions (IPCC AR6_WGI, confidence: high)
This leads to heterogeneity in regional changes and their associated uncertainties (IPCC AR6_WGI, confidence: high)
The intensity and frequency of cold spells in all Asian regions have been decreasing since the beginning of the 20th century (IPCC AR6_WGI, confidence: high)
Annual minimum temperatures on land have increased about three times more than global surface temperature since the 1960s, with particularly strong warming in the Arctic (IPCC AR6_WGI, confidence: high)
In general, CMIP5 and CMIP6 historical simulations are similar in their performance in simulating the observed climatology of extreme temperatures (IPCC AR6_WGI, confidence: high)
Irrigation and crop intensification have been shown to lead to a cooling in some regions, in particular in North America, Europe, and India (IPCC AR6_WGI, confidence: high)
Crop intensification, irrigation and no-till farming have attenuated increases in summer hot extremes in some regions, such as Central North America (IPCC AR6_WGI, confidence: medium)
Exceptions include lower confidence in the projected decrease in the intensity and frequency of cold extremes compared with the 1995–2014 baseline under 1.5°C of global warming (IPCC AR6_WGI, confidence: medium)
In most regions, changes in the magnitude of temperature extremes are proportional to global warming levels (IPCC AR6_WGI, confidence: high)
The probability of temperature extremes generally increases nonlinearly with increasing global warming levels (IPCC AR6_WGI, confidence: high)
Urbanization intensifies extreme precipitation, especially in the afternoon and early evening, over the urban area and its downwind region (IPCC AR6_WGI, confidence: medium)
Warming-induced thermodynamic change results in an increase in extreme precipitation, at a rate that closely follows the C-C relationship at the global scale (IPCC AR6_WGI, confidence: high)
Precipitation extremes are also affected by forcings other than changes in greenhouse gases, including changes in aerosols, land- use and land-cover change, and urbanization (IPCC AR6_WGI, confidence: medium)
Daily mean precipitation intensities have increased since the mid-20th century in a majority of land regions (IPCC AR6_WGI, confidence: high)
In Asia (Table 11.8), there is robust evidence that extreme precipitation has increased since the 1950s (IPCC AR6_WGI, confidence: high)
In Australasia (Table 11.11), available evidence has not shown an increase or a decrease in heavy precipitation over Australasia as a whole (IPCC AR6_WGI, confidence: medium)
There were increases in extreme precipitation in Tobago from 1985–2015 (Stephenson et al., 2014; Dookie et al., 2019) and decreases in south-western French Polynesia and the southern subtropics (IPCC AR6_WGI, confidence: low)
Human influence has contributed to the intensification of heavy precipitation in three continents where observational data are more abundant (IPCC AR6_WGI, confidence: high)
Heavy precipitation will likely increase by the end of the century under RCP8.5 in West Africa (Diallo et al., 2016; Dosio, 2016; Sylla et al., 2016; Abiodun et al., 2017; Akinsanola and Zhou, 2019; Dosio et al., 2019) and is projected to increase (IPCC AR6_WGI, confidence: high)
In north-east and central east Africa, extreme precipitation intensity is projected to increase across CMIP5, CMIP6 and CORDEX-CORE (IPCC AR6_WGI, confidence: high)
Agreement in projected changes by different models is low in regions of complex topography such as Hindu-Kush Himalayas (Roy et al., 2019), but CMIP5, CMIP6 and CORDEX-CORE simulations consistently project an increase in heavy precipitation in higher latitude areas, such as West and East Siberia, and Russian Far East (IPCC AR6_WGI, confidence: high)
Daily rainfall extremes are projected to increase at the 2.0°C global warming level (IPCC AR6_WGI, confidence: medium)
Increases in the intensity of extreme precipitation events at regional scales will depend on the amount of regional warming as well as changes in atmospheric circulation and storm dynamics leading to regional differences in the rate of heavy precipitation changes (IPCC AR6_WGI, confidence: high)
Changes in extreme precipitation may be used as a proxy to infer changes in some types of flash floods that are more directly related to extreme precipitation (IPCC AR6_WGI, confidence: high)
In summary, the seasonality of floods has changed in cold regions where snowmelt dominates the flow regime in response to warming (IPCC AR6_WGI, confidence: high)
In summary, global hydrological models project a larger fraction of land areas to be affected by an increase in river floods than by a decrease in river floods (IPCC AR6_WGI, confidence: medium)
Thermodynamic processes are thus the main driver of drought changes in a warming climate (IPCC AR6_WGI, confidence: high)
Drought events are the result of dynamic and/or thermodynamic processes, with thermodynamic processes being the main driver of drought changes under human-induced climate change (IPCC AR6_WGI, confidence: high)
Several meteorological and agricultural and ecological drought events have been attributed to human-induced climate change, even in regions where no long-term changes are detected (IPCC AR6_WGI, confidence: medium)
However, a lack of attribution to human-induced climate change has also been shown for some events (IPCC AR6_WGI, confidence: medium)
In summary, human influence has contributed to increases in agricultural and ecological droughts in the dry season in some regions due to increases in evapotranspiration (IPCC AR6_WGI, confidence: medium)
The increases in evapotranspiration have been driven by increases in atmospheric evaporative demand induced by increased temperature, decreased relative humidity and increased net radiation over affected land areas (IPCC AR6_WGI, confidence: high)
Human- induced climate change has contributed to global-scale change in low flow, but human water management and land-use changes are also important drivers (IPCC AR6_WGI, confidence: medium)
Projected changes show increases in drought frequency and intensity in several regions as function of global warming (IPCC AR6_WGI, confidence: high)
There are also substantial increases in drought hazard probability from 1.5°C to 2°C global warming and for further additional increments of global warming (IPCC AR6_WGI, confidence: high)
In Asia, most AR6 regions show low confidence in projected changes in meteorological droughts at 1.5°C and 2°C of global warming, with a few regions displaying a decrease in meteorological droughts at 4°C of global warming (RAR, ESB, RFE, ECA; medium confidence), although there is a projected increase in meteorological droughts in South East Asia at 4°C (IPCC AR6_WGI, confidence: medium)
The overall evidence suggests an increase in meteorological drought at 4°C in the WCE region (IPCC AR6_WGI, confidence: medium)
The assessment shows that several regions will be affected by more severe agricultural and ecological droughts even if global warming is stabilized at 2°C, including MED, WSAF, SAM and SSA (high confidence), and ESAF, MDG, EAU, SAU, SCA, CAR, NSA, NES, SWS, WCE, NCA, WNA and CNA (IPCC AR6_WGI, confidence: medium)
NEAF, SAS are also projected to experience less agricultural and ecological drought with global warming (IPCC AR6_WGI, confidence: medium)
In summary, more regions are affected by increases in agricultural and ecological droughts with increasing global warming (IPCC AR6_WGI, confidence: high)
New evidence strengthens the SR1.5 conclusion that even relatively small incremental increases in global warming (+0.5°C) cause a worsening of droughts in some regions (IPCC AR6_WGI, confidence: high)
A larger number of regions are projected to be affected by more severe agricultural and ecological droughts at 2°C of global warming, including MED, WSAF, SAM and SSA (high confidence), and ESAF, MDG, EAU, SAU, SCA, CAR, NSA, NES, SWS, WCE, NCA, WNA and CNA (IPCC AR6_WGI, confidence: medium)
Enhanced atmospheric CO 2 concentrations lead to enhanced water-use efficiency in plants (IPCC AR6_WGI, confidence: medium)
The SR1.5 (Chapter 3, Hoegh-Guldberg et al., 2018) essentially confirmed the AR5 assessment of TCs and ETCs, adding that heavy precipitation associated with TCs is projected to be higher at 2°C compared to 1.5°C global warming (IPCC AR6_WGI, confidence: medium)
Global changes (blue shading) from top to bottom: (i) Increased mean and maximum rain rates in TCs, ETCs, and ARs [past ( low confidence due to lack of reliable data) and projected (high confidence)]; (ii) Increased proportion of stronger TCs [past ( medium confidence) and projected (high confidence)]; (iii) Decrease or no change in global frequency of TC genesis [past ( low confidence due to lack of reliable data) and projected (medium confidence)]; and (iv) Increased and decreased ETC wind speed, depending on the region, as storm tracks change [past ( low confidence due to lack of reliable data) and projected (IPCC AR6_WGI, confidence: medium)
Regional changes, from left to right: (i) Poleward TC migration in the western North Pacific and subsequent changes in TC exposure [past ( medium confidence) and projected (medium confidence)]; (ii) Slowdown of TC forward translation speed over the contiguous USA and subsequent increase in TC rainfall [past ( medium confidence) and projected (low confidence due to lack of directed studies)]; and (iii) Increase in mean and maximum SCS rain rate and increase in spring SCS frequency and season length over the contiguous USA [past ( low confidence due to lack of reliable data) and projected (IPCC AR6_WGI, confidence: medium)
However, higher-resolution models generally capture TC properties more realistically (IPCC AR6_WGI, confidence: high)
Models with realistic atmosphere– ocean interactions are generally better than atmosphere-only models at reproducing realistic TC evolutions (IPCC AR6_WGI, confidence: high)
Subsequent literature assessed in the Climate Science Special Report (Kossin et al., 2017) led to the assessment of the observed tornado activity over the 2000s in the USA, with a decrease in the number of days per year with tornadoes and an increase in the number of tornadoes on these days (IPCC AR6_WGI, confidence: medium)
Climate models consistently project environmental changes that would support an increase in the frequency and intensity of severe thunderstorms that combine tornadoes, hail, and winds (IPCC AR6_WGI, confidence: high)
There is an upward trend in the frequency and intensity of extreme precipitation events in the USA (IPCC AR6_WGI, confidence: high)
There is medium confidence that the mean annual number of tornadoes in the USA has remained relatively constant, but their variability of occurrence has increased since the 1970s, particularly over the 2000s, with a decrease in the number of days per year, and an increase in the number of tornadoes on these days (IPCC AR6_WGI, confidence: high)
In summary, the average and maximum rain rates associated with severe convective storms increase in a warming world in some regions, including the USA (IPCC AR6_WGI, confidence: high)
The frequency of severe convective storms in spring is projected to increase in the USA, leading to a lengthening of the severe convective storm season (IPCC AR6_WGI, confidence: medium)
There is significant uncertainty about projected regional changes in tornadoes, hail, and lightning due to limited analysis of simulations using convection-permitting models (IPCC AR6_WGI, confidence: high)
Based on the consistency of these studies, it is likely that medicanes will decrease in frequency, while the strongest medicanes become stronger under warming scenario projections (IPCC AR6_WGI, confidence: medium)
In summary, the observed intensity of extreme winds is becoming less severe in the low to mid-latitudes, while becoming more severe in high latitudes poleward of 60 degrees (IPCC AR6_WGI, confidence: low)
Projected changes in the frequency and intensity of extreme winds are associated with projected changes in the frequency and intensity of TCs and ETCs (IPCC AR6_WGI, confidence: medium)
Concurrent extreme events at different locations, but possibly affecting similar sectors (e.g., breadbaskets) in different regions, will become more frequent with increasing global warming, in particular above +2°C of global warming (IPCC AR6_WGI, confidence: high)
Both the ENSO amplitude and the frequency of high-magnitude events since 1950 is higher than over the pre-industrial period (IPCC AR6_WGI, confidence: medium)
Climate change has already altered CID profiles and resulted in shifts in the magnitude, frequency, duration, seasonality and spatial extent of associated indices (IPCC AR6_WGI, confidence: high)