rlacombe/ClimateX huggingface dataset:
The greater climate velocities inside marine hotspots exposes their species to greater climate-induced pressures inside than outside hotspots (IPCC AR6_WGII, confidence: high)
The differences between temperatures inside and outside of hotspots narrow with increasing warming (IPCC AR6_WGII, confidence: medium)
Of the 6116 projections for more than 2700 species assessed in biodiversity hotspots, ~44% were found to be at high extinction risk, and ~24% at very high extinction risk due to climate change (IPCC AR6_WGII, confidence: medium)
For a given evidence and agreement statement, different confidence levels can be assigned, but increasing levels of evidence and degrees of agreement are correlated with increasing confidence.endemic species than other native species (IPCC AR6_WGII, confidence: high)
For these endemic species, considering all scenarios and time periods evaluated, ~100% on islands, ~84% on mountains, ~12% on continents (medium confidence) and ~54% in the ocean (notably the Mediterranean) (IPCC AR6_WGII, confidence: low)
With further warming, increasingly high risks of local and global extinctions are projected in biodiversity hotspots from climate-related stressors (IPCC AR6_WGII, confidence: high)
Adaptation options for biodiversity (e.g., expanding fully protected areas, restoration and sustainable use practices) are as applicable inside biodiversity hotspots as outside (IPCC AR6_WGII, confidence: high)
Thus, terrestrial biodiversity hotspots have been warming slightly less, and marine hotspots considerably more than non-hotspots (IPCC AR6_WGII, confidence: medium)
This suggests that, if these areas are subject to increased velocities, they will lose species that are not able to disperse fast enough to cope with the pace of climate change (IPCC AR6_WGII, confidence: medium)
Climate velocities are 47% (Myers), 29% (G200, terrestrial) and 10% (G200, freshwater) lower inside biodiversity hotspots than outside, respectively (Kocsis et al., 2021), but are 69% higher inside marine hotspots than outside (IPCC AR6_WGII, confidence: medium)
Marine species tend to follow climate velocities more closely than terrestrial species (IPCC AR6_WGII, confidence: high)
The subtropics are then source areas of species that shift to temperate latitudes and so forth, such that observed impacts in marine biodiversity hotspots are largely attributable to species range shifts (IPCC AR6_WGII, confidence: high)
Because marine climate velocities are significantly greater within than outside hotspots, marine hotspots are especially prone to species redistributions (IPCC AR6_WGII, confidence: medium)
Thus, as already observed in the oceans around the equator, the loss of species in low latitudes will continue with future climate warming (IPCC AR6_WGII, confidence: high)
Since the 1950s, marine species richness has shifted poleward in the Northern Hemisphere, increased in mid-latitudes and declined at the equator in concert with ocean warming (IPCC AR6_WGII, confidence: medium)
Climate- driven altitudinal shifts are common on land (high confidence) (Lenoir and Svenning, 2015; Steinbauer et al., 2018), and depth shifts in the ocean may occur but are little studied (IPCC AR6_WGII, confidence: low)
While climate-induced range expansions can be viewed as opportunities for increasing regional biodiversity, range contractions adversely affect biodiversity through regional extirpations (IPCC AR6_WGII, confidence: high)
Modelled temperatures are projected to continue to be the highest in the tropics, indicating where there are more thermally stressful conditions for more species (IPCC AR6_WGII, confidence: high)
By the end of this century, all terrestrial biodiversity hotspots in Central and South America, Africa, India and southern and eastern Asia (including the Indo–West Pacific islands) are projected to experience climates unprecedented in their species’ evolutionary history (IPCC AR6_WGII, confidence: medium)
Based on WGI Interactive Atlas data (Gutiérrez et al., 2021), global warming is projected to affect terrestrial hotspots less than non- hotspot areas: 80% less for Myers and 95–96% less for G200 terrestrial and freshwater hotspots at global warming of 1.5°C–3°C (IPCC AR6_WGII, confidence: medium)
In contrast, warming is projected to be 12–13% greater inside than outside marine hotspots (IPCC AR6_WGII, confidence: medium)
Precipitation is generally projected to increase more in terrestrial and freshwater biodiversity hotspots compared to outside them (IPCC AR6_WGII, confidence: low)
The exception is Myers hotspots, which are projected to have, on average, ~28% less precipitation at 1.5°C warming, but ~33% more at 2°C and ~65% more at 3°C (IPCC AR6_WGII, confidence: low)
CCP1.2.1.2.2 Projected impacts on biodiversity Biodiversity hotspots are expected to be especially vulnerable to climate change because their endemic species have smaller geographic ranges (IPCC AR6_WGII, confidence: high)
All measures of biodiversity were found to be negatively impacted by projected climate change, namely, species abundance, diversity, area, physiology and fisheries catch potential (IPCC AR6_WGII, confidence: medium)
However, introduced species’ responses were neutral to positive (IPCC AR6_WGII, confidence: medium)
Land plants, insects, birds, reptiles and mammals were all projected to be negatively affected (medium confidence), as well as fish, coral reef, benthic, planktonic and other marine species (IPCC AR6_WGII, confidence: medium)
Of the 6116 projections for more than 2,700 species assessed in biodiversity hotspots, ~44% were found to be at high extinction risk, and ~24% at very high extinction risk due to climate change (Manes et al., 2021) (IPCC AR6_WGII, confidence: medium)
CCP1 2133Biodiversity Hotspots Cross-Chapter Paper 1 and ocean (IPCC AR6_WGII, confidence: medium)
This and previous assessments indicate that, while climate change varies spatially and taxa may respond differently, a loss of biodiversity is projected across all terrestrial hotspots (IPCC AR6_WGII, confidence: high)
CCP1.2.1.3 Compounding and Cascading Effects All biodiversity hotspots are already impacted, to differing degrees, by human activities (IPCC AR6_WGII, confidence: high)
Thus, climate change impacts on biodiversity hotspots are compounded by other anthropogenic impacts, increasing the vulnerability and reducing the resilience of biodiversity to climate change (IPCC AR6_WGII, confidence: very high)
Moreover, the present rates of species loss due to human activities are 130 times greater than those projected under future climate change (IPCC AR6_WGII, confidence: medium)
Marine systems are also vulnerable to cumulative human impacts, which can be direct (e.g., pollution, overfishing) and indirect (altered food webs) (IPCC AR6_WGII, confidence: very high)
Although there is a strong overlap of non-climatic and climatic impacts in marine ecosystems (Blowes et al., 2019; Bowler et al., 2020), the effects suggest that climate change impacts are most severe in tropical and northern high-latitude seas (IPCC AR6_WGII, confidence: high)
Temperature-driven range shifts and range expansions are projected to also lead to cascading effects on marine biodiversity through ecological interactions (IPCC AR6_WGII, confidence: high)
In Central and South America, observed impacts within Mesoamerica (H15, 16) and the Tropical Andes hotspots (H26, 27, 28, 32, 33) comprise upward altitudinal range shifts of birds, frogs, beetles and butterflies (Narins and Meenderink, 2014; Molina-Martínez et al., 2016; Moret et al., 2016; Freeman et al., 2018) (IPCC AR6_WGII, confidence: medium)
A shift of the Guianan-Amazon mangroves (H37) to higher grounds inland was attributed to the effects of observed sea level rise (IPCC AR6_WGII, confidence: low)
Range shifts in birds have been observed at higher elevations (IPCC AR6_WGII, confidence: medium)
Warming and drying trends have historically been shown to reduce the range of the Ethiopian wolf (Canis simensis), and they interact with land use pressures in the Ethiopian hotspot (H68) (Sintayehu, 2018) and plant species richness in the Cape Fynbos (H65) of southern Africa to reduce post-wildfire recruitment (IPCC AR6_WGII, confidence: low)
Observed impacts in Asia were mostly restricted to the Himalaya (H95, 98, 99), Sundaland (H109, 110, 111, 112, 117, 118) and Indo- Burma (H105, 106, 107, 114, 115) hotspots, showing negative impacts through increased invasion by exotic plants, decreased suitable area for endemic species and significant changes in phenology (IPCC AR6_WGII, confidence: medium)
In Australia, climate change has been implicated in: drought-induced canopy dieback across a range of forest and woodland types due to decades of declining rainfall in the southwestern hotspot (H133); fires in the palaeo-endemic pencil pine forests (Tasmania H142); declines in vertebrates in the Australian Wet Tropics World Heritage Area, which overlaps with the eastern part of the northern Australia hotspot (H131), related to warming and increased length of the dry season; and declines in grass and increases in shrubs in the Bogong High Plains (IPCC AR6_WGII, confidence: high)
The Australian Alps have seen increased species diversity following retreat of the snow line (Slatyer, 2010), replacement of long-lived trees by short-lived shrubs following multiple wildfires (Zylstra, 2018), and changing ecological interactions due to climate-related snow loss, drought and fires (IPCC AR6_WGII, confidence: high)
One positive observation was the high resilience to recovery of intact forest ecosystems to tropical cyclones within Caribbean (H20) and Pacific islands (IPCC AR6_WGII, confidence: medium)
About 85% of projections for assessed species showed a negative impact of climate change (IPCC AR6_WGII, confidence: high)
Projected impacts include contraction or loss of species’ geographic range, loss of diversity and high species turnover (IPCC AR6_WGII, confidence: high)
Climate change may also benefit invasive plant species in terms of range expansion (Wang et al., 2017) and physiology (de Faria et al., 2018) in the region.In European biodiversity hotspots, about 75% of projections for assessed species showed a negative impact of climate change, with ~30% at very high risk of extinction (IPCC AR6_WGII, confidence: medium)
Increased wildfire size and frequency is projected to have a strong effect on the Mediterranean basin (H216) ecosystems (IPCC AR6_WGII, confidence: medium)
Range reductions have been projected for endemic plants (Pérez-García et al., 2013; Casazza et al., 2014), reptiles (Ahmadi et al., 2019), birds (Abolafya et al., 2013) and insects (Sánchez-Guillén et al., 2013) (IPCC AR6_WGII, confidence: medium)
In African biodiversity hotspots, about 80% of projections for assessed species showed a negative impact of climate change, with ~10% at very high risk of extinction, especially of endemic species including birds, plants, bees across several taxa and hotspots if warming exceeds 2°C (IPCC AR6_WGII, confidence: high)
About ~70% of projections for assessed species showed a negative impact of climate change, with ~30% at very high risk of extinction (IPCC AR6_WGII, confidence: medium)
Impacts include species’ range changes, habitat loss for endemic plants, expansion of invasive species, decreased connectivity and overall species richness decline (IPCC AR6_WGII, confidence: high)
The few positive impacts of climate change were projected as increases in suitable habitat and distribution range for a few endangered plants and mammals (IPCC AR6_WGII, confidence: medium)
All projections for assessed species in Australia and New Zealand terrestrial biodiversity hotspots showed a negative impact of climate change, with half at very high risk of extinction (IPCC AR6_WGII, confidence: low)
While forest growth is projected to potentially increase due to carbon dioxide fertilization, this may be compromised by drought (IPCC AR6_WGII, confidence: low)
Seed production in native New Zealand beech forests is projected to increase due to climate warming, fuelling the abundance of invasive rats and stoats, which then predate native species and lead to loss of endemic fauna and flora (IPCC AR6_WGII, confidence: medium)
About 80% of projections for assessed terrestrial species within insular biodiversity hotspots showed a negative impact of climate change, with ~50% at very high risk of extinction, including 100% of endemic species (IPCC AR6_WGII, confidence: medium)
In addition to habitat loss and species range reductions, changes in precipitation are projected to be a major driver impacting tropical and subtropical island species (IPCC AR6_WGII, confidence: medium)
Compared to continents, island species are projected to undergo greater impacts from changing climate, especially birds and amphibians (IPCC AR6_WGII, confidence: high)
Of all biodiversity hotspots, island species face the highest proportion of extirpation risk at high elevations due to decreasing habitat area (e.g., Brown et al., 2015) and at low elevations from sea level rise, habitat loss and introduced species (IPCC AR6_WGII, confidence: medium)
CCP1 2143Biodiversity Hotspots Cross-Chapter Paper 1 CCP1.2.3.1 Observed Impacts An analysis of trends in 190 river basins in Australia found that stream- flows have been declining, including in the Central Australian (H194) and Kimberley (H191) hotspots, due to greater terrestrial plant uptake of water in response to climate-related increases in carbon dioxide (IPCC AR6_WGII, confidence: low)
CCP1.2.3.2 Projected Impacts Cold-water species are projected to lose habitat in Canada and this may apply in the Alaskan river (H143) and Russian Far East Lake Inle (H181) hotspots (IPCC AR6_WGII, confidence: medium)
In South America, in the Brazilian Amazon hotspot (H153, 154, 157), half the assessed fish species were considered sensitive to increased temperatures and reduced oxygen due to climate change (IPCC AR6_WGII, confidence: low)
In Europe, including the Mediterranean freshwater hotspots, climate change is projected to result in reduced river flow, low oxygen in summer, salinity incursions, further eutrophication and spread of invasive species, compromising the survival of native biodiversity (IPCC AR6_WGII, confidence: medium)
The longer growth season in the boreal and Arctic latitudes is projected to aid the invasion of exotic species, and increase lake stratification resulting in lower oxygen below the hypolimnion (IPCC AR6_WGII, confidence: medium)
An analysis of 1648 species of freshwater fish, amphibians, turtles, plants, molluscs, crayfish and dragonflies, projected ~6% of common and ~77% of rare species to lose 90% of their geographic range (IPCC AR6_WGII, confidence: low)
Thus, the areas where freshwater biodiversity is most threatened by climate change in Europe are in two of the three hotspots (high confidence).The African Rift Valley Lakes (H171), including Lakes Tanganyika and Turkana, are suffering from climate change influenced drought, po- tentially impacting freshwater biodiversity (IPCC AR6_WGII, confidence: medium)
Africa and Madagascar (H172) are projected to see a climate-driven 10% reduction in freshwater flow that is projected to threaten the survival of ~9% of freshwater-dependent fish and birds (IPCC AR6_WGII, confidence: low)
Climate change is projected to increase the extinction vulnerability of most freshwater fish in the western South Africa Cape hotspot (H170) (IPCC AR6_WGII, confidence: low)
In Asia, although climate change impacts on the Yangtze (H183) and Mekong river (H186) biodiversity hotspots have not been reported, they are subject to the range of human impacts of over-exploitation, pollution, water abstraction, altered flow regimes, habitat loss and spread of invasive species, which makes them more vulnerable to climate effects (IPCC AR6_WGII, confidence: medium)
The release of water from shrinking glaciers in Asia to some extent protects downstream freshwaters against drought, but half of these glaciers are projected to disappear by 2100 (IPCC AR6_WGII, confidence: medium)
In Australia, the Murray-Darling river basin occupies much of the Eastern Rivers hotspot (H195) and climate-related drought exacerbated by water abstraction is projected to drive declines in freshwater birds, fish and invertebrates (IPCC AR6_WGII, confidence: high)
A national scale analysis projected climate change to cause freshwater species range shifts, but no losses of species in this hotspot (IPCC AR6_WGII, confidence: low)
Marine heatwaves have increased over the past century, causing mass mortalities in the hotspots of the Mediterranean (H216), Great Barrier Reef (H236), western and southern Australia (H227, 228), northwest Atlantic (H207) and northeast Pacific (H197) (IPCC AR6_WGII, confidence: high)
The shift of thousands of species from equatorial latitudes since the 1950s has been attributed to climate warming (IPCC AR6_WGII, confidence: medium)
Climate change-related hazards, particularly marine heat events, have caused widespread coral bleaching and mass mortalities as the time between consecutive bleaching events decreases (IPCC AR6_WGII, confidence: high)
Coral reefs in some Indian Ocean hotspots (H230, 234) already exhibit net loss of coral reefs (IPCC AR6_WGII, confidence: low)
CCP1 2145Biodiversity Hotspots Cross-Chapter Paper 1 visible symptom of heat stress, warming has also induced restructuring of associated fish and invertebrate communities in the Great Barrier Reef (H236) (IPCC AR6_WGII, confidence: medium)
Although the number of coral species that are both exposed and vulnerable to climate hazards is greatest in the central Indo-Pacific, the proportion of corals at risk is greater in the lower diversity Caribbean hotspots (H209) (IPCC AR6_WGII, confidence: medium)
Some reef corals are able to acclimate to heatwaves (low confidence) (DeCarlo et al., 2019), and some have expanded their latitudinal ranges polewards (IPCC AR6_WGII, confidence: high)
The Mediterranean Sea hotspot (H216) is negatively affected by climate change (IPCC AR6_WGII, confidence: high)
Species entering via the Suez Canal from the Red Sea (H220) are facilitated by warming and lead to profound community changes (IPCC AR6_WGII, confidence: high)
Kelp forests are in decline in mid-latitudes due to warming and associated increased herbivory (IPCC AR6_WGII, confidence: medium)
Australia’s Great Barrier Reef (H236), kelp forests, seagrass meadows and mangroves (due to drought), have suffered mortalities due to climate change (IPCC AR6_WGII, confidence: medium)
However, while climate change is having measurable effects on kelp, the dominant effects on kelp projected to 2025 are fishing, through its effects on herbivores and predators (IPCC AR6_WGII, confidence: medium)
The distribution of krill has already contracted with ocean warming in the Southern Ocean (IPCC AR6_WGII, confidence: medium)
Paleo evidence supports projections of tropical biodiversity loss under high global warming (IPCC AR6_WGII, confidence: high)
Warm-water coral reefs are expected to decline with 1.5°C warming (very high confidence) (King et al., 2017; Bindoff et al., 2019) leading to systems with reduced biodiversity and structural complexity (IPCC AR6_WGII, confidence: high)
While some corals are expected to survive in deep ‘mesophotic’ reefs (Laverick and Rogers, 2019), the shallow coral reefs of today will not last the century if climate warming continues without mitigation (IPCC AR6_WGII, confidence: high)
Around Antarctica (H213), almost half of all species are endemic (Costello et al., 2010), and warming during this century is projected to cause a reduction in suitable thermal environment for 79% of its species (RCP8.5) (IPCC AR6_WGII, confidence: low)
Species richness in the northern polar hotspots is expected to increase substantially (IPCC AR6_WGII, confidence: high)
Where land barriers and other geographical limits to range shifts occur, limited dispersal and habitat fragmentation may also limit the capacity of some species to track climate velocities, such as in the Baltic Sea (H215) (Jonsson et al., 2018), Mediterranean Sea (H216) (Burrows et al., 2014; Arafeh- Dalmau et al., 2021) and Antarctica (H213) (IPCC AR6_WGII, confidence: medium)
Many of these hotspots are now faced with widespread fragmentation and habitat degradation (IPCC AR6_WGII, confidence: high)
Although mitigation can sharply reduce extinction risk associated with climate change (IPCC AR6_WGII, confidence: high)
Thus, in addition to mitigation, the literature consistently calls for reducing current non-climate impacts (e.g., habitat conversion, over-exploitation, hunting, fishing, wildfire, pollution, human-introduced invasive species) in order to increase biodiversity resilience to climate change (IPCC AR6_WGII, confidence: very high)
The main strategies to increase resilience rely on the combination of well-planned protected areas, restoration of degraded areas and the sustainable use of biodiversity (IPCC AR6_WGII, confidence: high)
On land, creating corridors for species is key for facilitating species movements (IPCC AR6_WGII, confidence: high)
Healthier marine ecosystems are more resilient to additional stressors, such as storms and climate change (IPCC AR6_WGII, confidence: high)
Extinction risk is lower when populations are larger and more genetically diverse, individuals are larger and older, and seabed habitats (e.g., coral, kelp, seagrass) are flourishing, as occurs in marine reserves (IPCC AR6_WGII, confidence: high)
Thus, a network of reserves representative of global biodiversity, helps attenuate the effects of climate change (IPCC AR6_WGII, confidence: medium)
However, the impacts of marine heatwaves on corals across marine reserves illustrates that enhanced resilience is not enough to protect against extreme and future climate change conditions (IPCC AR6_WGII, confidence: high)
If coastal management permits the expansion of mangroves inland with rising sea level, this will increase carbon sequestration because mangroves capture and preserve more carbon in their sediments than other terrestrial and marine forests and biomes (IPCC AR6_WGII, confidence: high)
Thus, the protection of existing natural habitats coupled with the restoration of the surrounding non-protected habitat can increase the effectiveness of adaptation strategies in terrestrial and freshwater hotspots (IPCC AR6_WGII, confidence: very high)
Islands have disproportionately higher rates of endemism and threat when compared to continents, with 80% of historical extinctions (since 1500 CE) having occurred on islands (IPCC AR6_WGII, confidence: high)
Current climate change projections suggest that insular species are particularly sensitive and, even at mild warming levels, substantial losses are expected (IPCC AR6_WGII, confidence: high)
Given islands’ characteristic high endemicity, current high threat levels and the fact that islands host almost half of all species currently considered to be at risk of extinction, especially at higher warming levels (IPCC AR6_WGII, confidence: high)
Unlike continental environments, insular species often have limited opportunities for autonomous adaptation from not having enough geographic space to shift their ranges to track suitable climatic conditions (IPCC AR6_WGII, confidence: high)
Intact island forests, for example, have shown rapid recovery rates after tropical cyclones, despite high levels of initial damage, especially in the Caribbean (IPCC AR6_WGII, confidence: medium)
However, this climate resilience will not be sustained under climate change, especially when coupled with habitat degradation (IPCC AR6_WGII, confidence: high)
Widespread unavailability of such data constrains accurate simulations of climatic variation within the small-scale mountainous and coastal regions of islands, associated with climate refugia and high habitat heterogeneity (IPCC AR6_WGII, confidence: high)
This is a key element contributing to the continued delay in development of robust adaptation strategies towards not only biodiversity conservation but other important cross-sectoral issues (IPCC AR6_WGII, confidence: medium)