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Abstract. The atmospheric circulation is a key area of uncertainty in climate model simulations of future climate change, especially in mid-latitude regions such as Europe where atmospheric dynamics have a significant role in climate variability. It has been proposed that the mid-Holocene was characterized in Europe by a stronger westerly circulation in winter comparable with a more positive AO/NAO, and a weaker westerly circulation in summer caused by anticyclonic blocking near Scandinavia. Model simulations indicate at best only a weakly positive AO/NAO, whilst changes in summer atmospheric circulation have not been widely investigated. Here we use a new pollen-based reconstruction of European mid-Holocene climate to investigate the role of atmospheric circulation in explaining the spatial pattern of seasonal temperature and precipitation anomalies. We find that the footprint of the anomalies is entirely consistent with those from modern analogue atmospheric circulation patterns associated with a strong westerly circulation in winter (positive AO/NAO) and a weak westerly circulation in summer associated with anti-cyclonic blocking (positive SCAND). We find little agreement between the reconstructed anomalies and those from 14 GCMs that performed mid-Holocene experiments as part of the PMIP3/CMIP5 project, which show a much greater sensitivity to top-of-the-atmosphere changes in solar insolation. Our findings are consistent with datamodel comparisons on contemporary timescales that indicate that models underestimate the role of atmospheric circulation in recent climate change, whilst also highlighting the importance of atmospheric dynamics in explaining interglacial warming.

Aim  To contribute to the intense debate surrounding the relative influence of climate and humans on Mediterranean‐region land cover over the past 6000 years, we assess the Holocene biogeography and vegetation history of southern Europe by means of an extensive pollen record dataset. Location  The Mediterranean biogeographical zone and neighbouring parts of Iberia, the Alps and Anatolia, between 30° N, 48° N, 10° W and 45° E. Methods  We compiled a southern European pollen record dataset using available pollen databases (124 sites) and other sources (74 sites), with improved spatial coverage and dating control compared with earlier studies. We used only those sites that had pollen data for both 0 ka and 6 ka. We reconstructed mid‐Holocene and present‐day biomes, arboreal pollen percentages and distribution and relative abundance of 11 key woody taxa, with anomaly maps. Results  Northern temperate forest biomes extended further south at the mid‐Holocene than at present, but not as far as earlier studies suggested. Sclerophyllous vegetation occurred along the Mediterranean coast throughout the region at 6 ka. Arboreal pollen percentages were up to 50% higher than at present. At 6 ka, Olea, Fagus and Juniperus had smaller distributions and/or abundances; Abies, Cedrus and both deciduous and evergreen Quercus had larger distributions and/or abundances; Phillyrea, Pistacia and Cistus showed minimal difference; and Pinus showed a cosmopolitan distribution with variable abundance. Main conclusions  Temporal difference analysis is more meaningful when only sites containing samples for all time slices are analysed. During the mid‐Holocene, southern Europe was more heavily forested with temperate vegetation than it is at present, but drought‐tolerant xeric vegetation was still widespread along the southern margins of the region. Although human land use may have caused the degradation of land between the mid‐Holocene and the present, the mere presence of xeric vegetation in the Mediterranean region does not require human impact. This challenges the commonly held belief that modern Mediterranean vegetation represents a ‘degraded’ state.

To assess quantitatively the age of the modern vegetated landscape of Europe and western Asia Minor, and to reconstruct Holocene dynamics in biomes and landscape openness, we convert pollen data into plant functional type (PFT) assemblages and interpolate the data in space and time with a 4D thin plate spline. We then assess overall vegetation change using the squared chord distance metric, changes in potential natural vegetation using the biomisation method, and changes in landscape openness by calculating the arboreal pollen PFT percentage. The age of the modern European vegetated landscape varies in space; while much of lowland Europe dates to *2,000 cal years BP, some areas have remained unchanged since the beginning of the Holocene; on average, the European vegetated landscape is *4,000 years old. Though the (PFT) assemblage became continuously more similar to present, biome assemblages changed in northern and southern Europe but stayed relatively constant in central Europe. Landscape openness as approximated by arboreal PFT % increased until the mid-Holocene and then returned to early-Holocene conditions by modern times.The temporally continuous dominance of forest biomes suggests climate remained favourable to forest cover across Europe throughout the Holocene. Nevertheless, arboreal PFT % decreased significantly between the mid-Holocene and the present, requiring a non-climatic explanation, which can be offered by disturbance from human activity. Thus, human activity may have been a main driver of European vegetation dynamics since the mid-Holocene, suggesting it should be included in future conceptions of ''natural'' European vegetation dynamics.

Sustaining the organisms, ecosystems and processes that underpin human wellbeing is necessary to achieve sustainable development. Here we define critical natural assets as the natural and semi-natural ecosystems that provide 90% of the total current magnitude of 14 types of nature’s contributions to people (NCP), and we map the global locations of these critical natural assets at 2 km resolution. Critical natural assets for maintaining local-scale NCP (12 of the 14 NCP) account for 30% of total global land area and 24% of national territorial waters, while 44% of land area is required to also maintain two global-scale NCP (carbon storage and moisture recycling). These areas overlap substantially with cultural diversity (areas containing 96% of global languages) and biodiversity (covering area requirements for 73% of birds and 66% of mammals). At least 87% of the world’s population live in the areas benefitting from critical natural assets for local-scale NCP, while only 16% live on the lands containing these assets. Many of the NCP mapped here are left out of international agreements focused on conserving species or mitigating climate change, yet this analysis shows that explicitly prioritizing critical natural assets and the NCP they provide could simultaneously advance development, climate and conservation goals.

The atmospheric circulation is a key area of uncertainty in climate model simulations of future climate change, especially in mid-latitude regions such as Europe where atmospheric dynamics have a significant role in climate variability. It has been proposed that the mid-Holocene was characterized in Europe by a stronger westerly circulation in winter comparable with a more positive AO/NAO, and a weaker westerly circulation in summer caused by anti-cyclonic blocking near Scandinavia. Model simulations indicate at best only a weakly positive AO/NAO, whilst changes in summer atmospheric circulation have not been widely investigated. Here we use a new pollen-based reconstruction of European mid-Holocene climate to investigate the role of atmospheric circulation in explaining the spatial pattern of seasonal temperature and precipitation anomalies. We find that the footprint of the anomalies is entirely consistent with those from modern analogue atmospheric circulation patterns associated with a strong westerly circulation in winter (positive AO/NAO) and a weak westerly circulation in summer (positive SCAND). We find little agreement between the reconstructed anomalies and those from a climate model simulation, which as with most model simulations shows a much greater sensitivity to local radiative forcing from top-of-the-atmosphere changes in solar insolation. Our findings are consistent with data-model comparisons on contemporary timescales that indicate that models underestimate the role of atmospheric circulation in climate change, whilst also highlighting the importance of atmospheric dynamics in explaining interglacial warming

The loss of forest is a leading cause of species extinction, and reforestation is 1 of 2 established interventions for reversing this loss. However, the role of reforestation for biodiversity conservation remains debated, and lacking is an assessment of the potential contribution that reforestation could make to biodiversity conservation globally. We conducted a spatial analysis of overlap between 1,550 forest-obligate threatened species' ranges and land that could be reforested after accounting for socioeconomic and ecological constraints. Reforestation on at least 43% (∼369 million ha) of reforestable area was predicted to potentially benefit threatened vertebrates. This is approximately 15% of the total area where threatened vertebrates occur. The greatest opportunities for conserving threatened vertebrate species are in the tropics, particularly Brazil and Indonesia. Although reforestation is not a substitute for forest conservation, and most of the area containing threatened vertebrates remains forested, our results highlight the need for global conservation strategies to recognize the potentially significant contribution that reforestation could make to biodiversity conservation. If implemented, reforestation of ∼369 million ha would also contribute substantially to climate-change mitigation, offering a way to achieve multiple sustainability commitments at once. Countries must now work to overcome key barriers (e.g., unclear revenue streams, high transaction costs) to investment in reforestation.

Non-technical summary Implicit in the UN's Sustainable Development Goal (SDG) Agenda is the notion that environmental sustainability is intertwined with, and underpins, the 17 Goals. Yet the language of the Goals, and their Targets and indicators is blind to the myriad ways in which nature supports people's health and wealth – which we argue represents a key impediment to progress. Using examples of nature–human wellbeing linkages, we assess the language of all 169 Targets to identify urgent research, policy, and action needed to spotlight and leverage nature's foundational role, to help enable truly sustainable development for all. Technical summary Nature's foundational role in helping achieve the SDGs is implicit rather than explicit in the language of SDGs Goals, Targets, and indicators. Drawing from the scientific literature describing how nature underpins human wellbeing, we carry out a systematic assessment of the language of all 169 Targets, categorizing which Targets are dependent upon nature for their achievement, could harm nature if attained through business-as-usual actions, or may synergistically benefit nature through their attainment. We find that half are dependent upon nature for their achievement – yet for more than two-thirds of those nature's role goes unstated and risks being downplayed or ignored. Moreover, while achieving the overwhelming majority of the 169 Targets could potentially benefit nature, more than 60% are likely to deliver ‘mixed outcomes’ – benefitting or harming nature depending on how they're achieved. Furthermore, of the 241 official indicators <5% track nature's role in achieving the parent Target. Our analysis provides insights important for increasing effectiveness across the SDG agenda regarding where to invest, how to enhance synergies and limit unanticipated impacts, and how to measure success. It also suggests a path for integrating the ‘nature that people need’ to achieve the SDGs into the CBD's post-2020 Global Biodiversity Framework. Social media summary Harmonizing links between the SDGs and the CBD's post-2020 Global Biodiversity Framework is vital for promoting sustainable development