An ecosystem service is a benefit derived by humanity that can be traced back to an ecological process. Although ecosystem services related to surface water have been thoroughly described, the ...relationship between atmospheric water and ecosystem services has been mostly neglected, and perhaps misunderstood. Recent advances in land-atmosphere modeling have revealed the importance of terrestrial ecosystems for moisture recycling. In this paper, we analyze the extent to which vegetation sustains the supply of atmospheric moisture and precipitation for downwind beneficiaries, globally. We simulate land-surface evaporation with a global hydrology model and track changes to moisture recycling using an atmospheric moisture budget model, and we define vegetation-regulated moisture recycling as the difference in moisture recycling between current vegetation and a hypothetical desert world. Our results show that nearly a fifth of annual average precipitation falling on land is from vegetation-regulated moisture recycling, but the global variability is large, with many places receiving nearly half their precipitation from this ecosystem service. The largest potential impacts for changes to this ecosystem service are land-use changes across temperate regions in North America and Russia. Likewise, in semi-arid regions reliant on rainfed agricultural production, land-use change that even modestly reduces evaporation and subsequent precipitation, could significantly affect human well-being. We also present a regional case study in the Mato Grosso region of Brazil, where we identify the specific moisture recycling ecosystem services associated with the vegetation in Mato Grosso. We find that Mato Grosso vegetation regulates some internal precipitation, with a diffuse region of benefit downwind, primarily to the south and east, including the La Plata River basin and the megacities of Sao Paulo and Rio de Janeiro. We synthesize our global and regional results into a generalized framework for describing moisture recycling as an ecosystem service. We conclude that future work ought to disentangle whether and how this vegetation-regulated moisture recycling interacts with other ecosystem services, so that trade-offs can be assessed in a comprehensive and sustainable manner.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Abstract
Climate change scenarios are typically based on trajectories of greenhouse gas emissions out into the future. These emissions are then incorporated into climate and earth system models to ...simulate pathways of global climate change. These pathways are often communicated as the average of numerous model simulations. Though essential for calculating the role of greenhouse gas emissions on the climate system, this approach inadvertently masks the fact that our future will conform to something akin to a single model simulation, or storyline—rather than the average of many simulations. Human responses to and interactions with these climate storylines will not necessarily be expected or rational. As such, potential social surprises could lead to multiple plotlines emerging from a single earth system storyline. Such social surprises are explored in three examples: net zero emissions achievement, low climate sensitivity, and solar climate intervention. Climate change scenarios are fundamentally dependent on policy pathways that in practice will be influenced by public perception and expectation. Thus, it is essential for climate change scenarios to recognize and incorporate the potential for heterogeneous social surprises to unexpected climate changes.
Urbanization is a global process that has taken billions of people from the rural countryside to concentrated urban centers, adding pressure to existing water resources. Many cities are specifically ...reliant on renewable freshwater regularly refilled by precipitation, rather than fossil groundwater or desalination. A precipitationshed can be considered the "watershed of the sky" and identifies the origin of precipitation falling in a given region. In this paper, we use this concept to determine the sources of precipitation that supply renewable water in the watersheds of the largest cities of the world. We quantify the sources of precipitation for 29 megacities and analyze their differences between dry and wet years. Our results reveal that 19 of 29 megacities depend for more than a third of their water supply on evaporation from land. We also show that for many of the megacities, the terrestrial dependence is higher in dry years. This high dependence on terrestrial evaporation for their precipitation exposes these cities to potential land-use change that could reduce the evaporation that generates precipitation. Combining indicators of water stress, moisture recycling exposure, economic capacity, vegetation-regulated evaporation, land-use change, and dry-season moisture recycling sensitivity reveals four highly vulnerable megacities (Karachi, Shanghai, Wuhan, and Chongqing). A further six megacities were found to have medium vulnerability with regard to their water supply. We conclude that understanding how upwind landscapes affect downwind municipal water resources could be a key component for understanding the complexity of urban water security.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Story-based futures serve an important role in climate change scenario development. Stories are particularly useful in exploring sea level rise possibilities, since we know many coastal areas are ...specifically vulnerable to accelerating rises in sea level. This discrete change in coastline is different from most other climate change impacts, and offers a clear basis for scientifically informed, future scenarios. We demonstrated this with a creative world-building effort set in Lagos, Nigeria in the year 2199. Further, we employed story-based scenario development, and created a learning-oriented serious game that allows users to experience a future Lagos in an open-ended, text-based adventure style. This collaborative process blended scientific research, story-telling, and artistic co-creation to iteratively construct the game “Lagos2199”. A pilot-use case of Lagos2199 is documented herein, with preliminary survey results from the student users. We present two core insights. First, we demonstrate how scientific projections regarding sea level rise can be leveraged as an entry point for world-building and scenario development of the future. Second, we show that such a scenario can be transformed into an immersive, story-based serious game to creatively communicate possible futures. Providing the next generation of citizens with fluency in both climate change impacts and how society will interact with such impacts is critical for providing adaptive capacity over the coming decades and centuries of accelerating global change.
Abstract
Climate change and unabated greenhouse gas emissions are increasing the possibility that the world will turn to climate intervention to curb ever-increasing global temperatures. This paper ...uses game theory to elucidate the conditions that might make a state more or less likely to begin unilateral, as opposed to internationally coordinated, climate intervention (UCI). We solve this game for several specific scientific, economic, and climatological conditions that change the likelihood of a government starting its own climate intervention deployment program without the participation of the broader international community. Specifically, we demonstrate that the plausibility of UCI is linked to perceptions of three key elements: (1) the effectiveness of climate intervention strategies, (2) the sensitivity of specific governments to punishment by other states, and (3) satisfaction with climate and weather in the present. We conclude by discussing how this formal game theory model informs the design of future Earth system model simulations of UCI, international agreements related to climate intervention, and the development of solar climate intervention technologies.
Pastoral communities living in the arid and semi-arid lands of Kenya raise livestock herds within highly patchy environments, and experience chronic food insecurity and inter-ethnic conflicts linked ...to resource access. For these primarily rural communities, livestock are a source of calories and income and are therefore crucial to achieving the United Nations’ Sustainable Development Goals (SDGs) associated with food security (SDG 2). Achieving sustainable improvements in household well-being in this region is contingent on understanding how diverse policy decisions complement or undermine the ability of pastoral households to raise livestock. Of near-term relevance is the question of reconciling food security with biodiversity conservation goals (SDG 15) across Kenya’s drylands, which are also known for their exceptional biodiversity. World over, protected areas are associated with diverse impacts on local communities. However, spatial variation in how these areas contribute to pastoral food security and household well-being across Kenya remain poorly understood. Using our newly developed model SPIRALL, we examined spatial variation in changes in household well-being that result when pastoral households across Kenya lose access to neighboring protected areas. SPIRALL is a country-scale, agent-based pastoral household decision-making model. We joined SPIRALL to L-Range, a model that simulates rangeland ecosystem functioning. The resulting coupled model simulates reciprocal interactions between pastoral households and the environment in Kenya and can be used as a scenario analysis tool to understand impacts of broadly defined policies on food security. Our scenario-based analysis showed that loss of protected-area access caused increases in rates of hunger, debt, and trans-boundary movements, particularly among non-sedentary and agropastoral households. These effects were spatially heterogeneous and influenced by county size and proximity to protected areas. We conclude by outlining the policy-implications result of the interactions between SDG 2 and SDG 15 in Kenya. We also highlight additional uses and avenues for improvement for SPIRALL.
Abstract
The human footprint index (HFI) is an extensively used tool for interpreting the accelerating pressure of humanity on Earth. Up to now, the process of creating the HFI has required ...significant data and modeling, and updated versions of the index often lag the present day by many years. Here we introduce a near-present, global-scale machine learning-based HFI (ml-HFI) which is capable of routine update using satellite imagery alone. We present the most up-to-date map of the HFI, and document changes in human pressure during the past 20 years (2000–2019). Moreover, we demonstrate its utility as a monitoring tool for the United Nations Sustainable Development Goal 15 (SDG15), ‘Life on Land’, which aims to foster sustainable development while conserving biodiversity. We identify 43 countries that are making progress toward SDG15 while also experiencing increases in their ml-HFI. We examine a subset of these in the context of conservation policies that may or may not enable continued progress toward SDG15. This has immediate policy relevance, since the majority of countries globally are not on track to achieve Goal 15 by the declared deadline of 2030. Moving forward, the ml-HFI may be used for ongoing monitoring and evaluation support toward the twin goals of fostering a thriving society and global Earth system.
Approaching moisture recycling governance Keys, Patrick W.; Wang-Erlandsson, Lan; Gordon, Line J. ...
Global environmental change,
07/2017, Letnik:
45
Journal Article
Recenzirano
Odprti dostop
•Governance of atmospheric moisture recycling is an Anthropocene governance gap.•Vegetation evaporates moisture that forms rainfall, which often falls in other countries.•Different types of moisture ...exchange require different governance principles.•Atmospheric moisture exchange among countries is categorized into four types.•Moisture recycling can partly be integrated into existing governance approaches.
The spatial and temporal dynamics of water resources are a continuous challenge for effective and sustainable national and international governance. The watershed is the most common spatial unit in water resources governance, which typically includes only surface and groundwater. However, recent advances in hydrology have revealed ‘atmospheric watersheds’ – otherwise known as precipitationsheds. Water flowing within a precipitationshed may be modified by land-use change in one location, while the effect of this modification could be felt in a different province, country, or continent. Despite an upwind country's ability to change a downwind country's rainfall through changes in land-use or land management, the major legal and institutional implications of changes in atmospheric moisture flows have remained unexplored. Here we explore potential ways to approach what we denote as moisture recycling governance. We first identify a set of international study regions, and then develop a typology of moisture recycling relationships within these regions ranging from bilateral moisture exchange to more complex networks. This enables us to classify different types of possible governance principles and relate those to existing land and water governance frameworks and management practices. The complexity of moisture recycling means institutional fit will be difficult to generalize for all moisture recycling relationships, but our typology allows the identification of characteristics that make effective governance of these normally ignored water flows more tenable.
Regulatory agencies have long adopted a three‐tier framework for risk assessment. We build on this structure to propose a tiered approach for resilience assessment that can be integrated into the ...existing regulatory processes. Comprehensive approaches to assessing resilience at appropriate and operational scales, reconciling analytical complexity as needed with stakeholder needs and resources available, and ultimately creating actionable recommendations to enhance resilience are still lacking. Our proposed framework consists of tiers by which analysts can select resilience assessment and decision support tools to inform associated management actions relative to the scope and urgency of the risk and the capacity of resource managers to improve system resilience. The resilience management framework proposed is not intended to supplant either risk management or the many existing efforts of resilience quantification method development, but instead provide a guide to selecting tools that are appropriate for the given analytic need. The goal of this tiered approach is to intentionally parallel the tiered approach used in regulatory contexts so that resilience assessment might be more easily and quickly integrated into existing structures and with existing policies.
Understanding vulnerabilities of continental precipitation to changing climatic conditions is of critical importance to society at large. Terrestrial precipitation is fed by moisture originating as ...evaporation from oceans and from recycling of water evaporated from continental sources. In this study, continental precipitation and evaporation recycling processes in the Earth system model GFDL-ESM2G are shown to be consistent with estimates from two different reanalysis products. The GFDL-ESM2G simulations of historical and future climate also show that values of continental moisture recycling ratios were systematically higher in the past and will be lower in the future. Global mean recycling ratios decrease 2%–3% with each degree of temperature increase, indicating the increased importance of oceanic evaporation for continental precipitation. Theoretical arguments for recycling changes stem from increasing atmospheric temperatures and evaporative demand that drive increases in evaporation over oceans that are more rapid than those over land as a result of terrestrial soil moisture limitations. Simulated recycling changes are demonstrated to be consistent with these theoretical arguments. A simple prototype describing this theory effectively captures the zonal mean behavior of GFDL-ESM2G. Implications of such behavior are particularly serious in rain-fed agricultural regions where crop yields will become increasingly soil moisture limited.
Celotno besedilo
Dostopno za:
BFBNIB, DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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