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In this paper the basic geophysical and ecological principles are jointly analyzed that allow the landmasses of Earth to remain moistened sufficiently for terrestrial life to be possible. 1. Under gravity, land inevitably loses water to the ocean. To keep land moistened, the gravitational water runoff must be continuously compensated by the atmospheric ocean-to-land moisture transport. Using data for five terrestrial transects of the International Geosphere Biosphere Program we show that the mean distance to which air fluxes can transport moisture over non-forested areas, does not exceed several hundred kilometers; precipitation decreases exponentially with distance from the ocean. 2. In contrast, precipitation over extensive natural forests does not depend on the distance from the ocean along several thousand kilometers, as illustrated for the Amazon and Yenisey river basins and Equatorial Africa. This points to the existence of an active biotic pump transporting atmospheric moisture inland from the ocean. 3. Physical principles of the biotic moisture pump are investigated based on the previously unstudied properties of atmospheric water vapor, which can be either in or out of aerostatic equilibrium depending on the lapse rate of air temperature. A novel physical principle is formulated according to which the low-level air moves from areas with weak evaporation to areas with more intensive evaporation. Due to the high leaf area index, natural forests maintain high evaporation fluxes, which support the ascending air motion over the forest and "suck in" moist air from the ocean, which is the essence of the biotic pump of atmospheric moisture. In the result, the gravitational runoff water losses from the optimally moistened forest soil can be fully compensated by the biotically enhanced precipitation at any distance from the ocean. 4. It is discussed how a continent-scale biotic water pump mechanism could be produced by natural selection acting on individual trees. 5. Replacement of the natural forest cover by a low leaf index vegetation leads to an up to tenfold reduction in the mean continental precipitation and runoff, in contrast to the previously available estimates made without accounting for the biotic moisture pump. The analyzed body of evidence testifies that the long-term stability of an intense terrestrial water cycle is unachievable without the recovery of natural, self-sustaining forests on continent-wide areas.
The physical principle that the low-level air moves from areas with weak evaporation to areas with more intensive evaporation provides clues for the observed patterns of atmospheric circulation. Black arrows: evaporation flux, arrow width schematically indicates the magnitude of this flux (evaporative force). Empty arrows: horizontal and ascending fluxes of moisture-laden air in the lower atmosphere. Dotted arrows: compensating horizontal and descending air fluxes in the upper atmosphere; after condensation of water vapor and precipitation they are depleted of moisture. (a) Deserts: evaporation on land is close to zero, so the low-level air moves from land to the ocean year round, thus “locking” desert for moisture. (b) Winter monsoon: evaporation from the warmer oceanic surface is larger than evaporation from the colder land surface; the low-level air moves from land to the ocean. (c) Summer monsoon: evaporation from the warmer land surface is larger than evaporation from the colder oceanic surface; the low-level air moves from ocean to land. (d) Hadley circulation (trade winds): evaporation is more intensive on the equator, where the solar flux is larger than in the higher latitudes; low-level air moves towards the equator year round; seasonal displacements of the convergence zone follow the displacement of the area with maximum insolation. (e) Biotic pump of atmospheric moisture: evaporation fluxes regulated by natural forests exceed oceanic evaporation fluxes to the degree when the arising ocean-to-land fluxes of moist air become large enough to compensate losses of water to runoff in the entire river basin year round.
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... Increase in ET, mainly from the valley forest enhances the total amount of precipitation, and may further increase the frequency of EREs in future. Forests act as a massive biotic pump of water vapour to the atmosphere that drives continentalscale hydrological cycle (Makarieva and Gorshkov 2007, Sheil and Murdiyarso 2009, Spracklen et al 2012, Makarieva et al 2014, Wright et al 2017. Besides, the enhanced control of vegetation on terrestrial energy fluxes, recent evidence shows the emerging role of forest ecophysiology in global hydrological cycle (Guerrieri et al 2019, Mathias and Thomas 2021). ...
... Valley forests, through regional-local transpiration-condensation cycle are known to sustain the convective system for a longer period (Makarieva and Gorshkov 2007, Sheil and Murdiyarso 2009, Makarieva et al 2014, Wright et al 2017. Thus, it is likely that increase in forest ET could augment frequent development of deep convections during convective season. ...
... Increased vertical pressure gradient resulting from condensation helps to maintain the convective systems and set the stage for the development of deep convection by drawing moist air from adjacent valleys. This would support a gradual increase in the moist static energy over the valleys, which would enhance convection and cumulus cloud development (Makarieva and Gorshkov 2007, Sheil and Murdiyarso 2009, Makarieva et al 2014, Ellison et al 2017, Wright et al 2017. ...
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Warming-induced expansion in vegetation coverage and activity can accelerate the montane hydrological regimes. However, the climate impacts on ecohydrology of forested valleys of the Himalaya are uncertain. In this study, utilizing results of about three centuries of cellulose isotope chronologies (δ13C and δ18O) of dominant tree species, geo-chronological proxies, bio-geophysical dataset and simulations including satellite observations, we show an activation in the ecophysiological processes including evapotranspiration since the 1950s. Observation suggests rapid greening, while isotopic records indicate enhanced assimilation and transpiration in deciduous species vis-à-vis conifers post 1950s. Given strong vegetation-precipitation feedback and superimposed on the increasing trends of conducive atmospheric factors affecting valley-scale convective processes, intensification in forest evapotranspiration is manifesting in a progressive enhancement in extreme rainfall events (EREs) since the last few decades. Results suggest that representation of ecophysiological processes and dynamics of seasonal moisture loading in observational and modelling framework is critical for understanding EREs under climate change.
... The issues of periods of drought, the history of droughts and extreme rainfall events in Europe are addressed in great details in many articles, e.g., (Ionita et al., 2017;Hanel et al., 2018;Svoboda et al., 2017). Our approach works with more integrated concepts, such as: Short Water Cycle (Pokorny, 2019), Overheated landscape (Hesslerova et al., 2018), air rivers (Makarieva and Gorshkov, 2007;Hesslerova et al., 2019). ...
... The introduced cycle was confirmed, e.g., in (Hesslerova et al., 2019) where the principal effect of temperature increase on landscape dehydration was related to the destruction of forests (Makarieva and Gorshkov, 2007). This sequence is associated with a key question: Why did not rain at the beginning of this loop? ...
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The large ecosystems (region, country, and planet) have many properties common with complex systems. The main such characteristics include dynamic instability (e.g. weather dependence), weak causality (many possible causes per event) and event driven behavior (especially in arid and semi-arid areas). This paper focuses attention on modeling ecosystems by approaches used for complex systems. When modeling complex ecosystems, we usually encounter the following difficulties: partiality, large amounts of data and uncertainties of conclusions. It can be said that none of the known approaches solves these difficulties perfectly. The most common is the physical approach, sometimes reinforced by statistical procedures. The physical approach to modeling leads to a complicated description of phenomena associated with relatively simple geometry. A complicated description usually requires a large amount of data (measured or simulated) and thus more complicated calculations. If we assume emergences in the ecosystem, a physical approach is not appropriate at all. In the presented article we apply the approach of so-called structural invariants, which has the opposite properties: a simple description of phenomena associated with a more complex geometry (in our case pre geometry). It does not require as much data and calculations are simple. The price paid is a qualitative interpretation of the results, which carries a special type of uncertainty. The structural invariant used in the article is the invariant Matroid and Bases of Matroid (M, BM) in combination with Ramsey graph theory. In addition, the article introduces a calculus that describes the emergent phenomenon using two quantities - the power of the emergent phenomenon and the complexity of the structure that is associated with this phenomenon. The developed method is used for a novel application of modeling the process of desertification of Earth. In this approach, we understand desertification as an emergent evolutionary operation of the Earth's development. In the sequence of two large previous emergences (warming of the Earth about 11,700 years ago and drying of the earth beginning about 6000 years ago), the time of possible further emergences related to the “desert expansion” operation is calculated. The second application of the method is the analysis of the operation “violation of Short Water Cycle” in the landscape and its possible contribution to the desertification.
... Water vapour-saturated air slowly rises and reaches the dew point, creating local afternoon/evening rainfall, returning some of the evaporated water to the surface. A (partially) closed water cycle is formed (Makarieva and Gorshkov, 2007). It is important to distinguish between drying of the landscape caused by overheated air, and evapotranspiration with a local cooling effect which "recycles" water locally (Huryna et al. 2014;Pokorný et al. 2016;Hesslerová et al. 2019;Pokorný 2019). ...
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In eastern Germany, the Czech Republic, and Slovakia, historic policies led to large, monocropped agricultural landscapes resulting in degradation of traditional landscapes. In the last 20 years, the expansion of urban and industrial areas has added to this degradation. The growing interest in nature‐based solutions, including water‐retention measures, is a response to reversing landscape degradation, rejuvenating ecosystem services, and mitigating the impacts of large‐scale commercial agriculture and climate change. In this study, the costs and benefits of water‐retention measures in east Germany, the Czech Republic, and Slovakia are assessed. Results indicate that water‐retention measures offer increased water availability over all land use classes assessed, help increase crop productivity, and aid in landscape cooling. Croplands are suggested as being the best value for money, offering the greatest volume potentials (mean = 88 million m3), cooling effects (mean = ‐1.6°C), and productivity gains (mean = €66 million yr‐1), while also being the cheapest to implement per unit area. Differing policies in the three states will likely result in non‐uniform selection or implementation of measures. Future work should focus on local‐level studies offering greater practical messages beyond the regional‐level analysis conducted here. This work contributes to the growing body of literature assessing the costs and benefits of water‐retention measures, including the potential for landscape cooling, lowering temperature gradients, and ecosystem restoration. As the world urbanises, and as more land is converted to homogeneous cropland, such measures may prove critical in mitigating climate change, landscape drying, flood runoff, and soil and nutrient loss. This article is protected by copyright. All rights reserved.
... Tree restoration could locally enhance convergence, cloud cover and precipitation and change the travelling direction and distance of atmospheric moisture 18,[41][42][43] . Research suggests that forests could even impact large-scale wind patterns and draw atmospheric moisture from the oceans to the continents 44,45 , although the importance of this effect is still debated. These different feedbacks are poorly understood and difficult to incorporate in the present study because most evaporation-recycling models rely on meteorological reanalysis data, which are valid only under current land-cover conditions. ...
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Tree restoration is an effective way to store atmospheric carbon and mitigate climate change. However, large-scale tree-cover expansion has long been known to increase evaporation, leading to reduced local water availability and streamflow. More recent studies suggest that increased precipitation, through enhanced atmospheric moisture recycling, can offset this effect. Here we calculate how 900 million hectares of global tree restoration would impact evaporation and precipitation using an ensemble of data-driven Budyko models and the UTrack moisture recycling dataset. We show that the combined effects of directly enhanced evaporation and indirectly enhanced precipitation create complex patterns of shifting water availability. Large-scale tree-cover expansion can increase water availability by up to 6% in some regions, while decreasing it by up to 38% in others. There is a divergent impact on large river basins: some rivers could lose 6% of their streamflow due to enhanced evaporation, while for other rivers, the greater evaporation is counterbalanced by more moisture recycling. Several so-called hot spots for forest restoration could lose water, including regions that are already facing water scarcity today. Tree restoration significantly shifts terrestrial water fluxes, and we emphasize that future tree-restoration strategies should consider these hydrological effects.
... Para edificios de varios pisos, los arreglos de sistemas multitanques en cascada de cosecha de agua lluvia (SMTCCALL) que disminuyen la cantidad de volumen de agua de necesario bombeo, al alimentar los tanques y suministrar por gravedad a los distintos usos(Sendanayake, 2010).Sin embargo, en última instancia, son las características locales -como la oferta y la demanda de agua de lluvia, el tipo de edificio (de una sola planta o de varias plantas), el diseño de subsistemas SCALL, el diseño del sistema de plomería de agua potable, la intensidad de la energía del agua de la ciudad, entre otros factores-las que determinarán si los rendimientos ambientales y económicos de los SCALL son aceptables. Es decir, el mejoramiento de la eficiencia de los SCALL sigue siendo un traje diseñado a la medida del usuario.Por tal razón, es menester analizar las características locales que son determinantes para la valoración de potenciales de eficiencias energéticas y de ahorro de agua; así, entonces, la oferta de agua lluvia en Bogotá está sujeta en gran medida a los determinantes climáticos del bosque tropical andino contiguo a la selva del Amazonas, la cual determina las cantidades de lluvia conjuntamente con los fenómenos que produce la Oscilación Sur (ENSO) de El Niño y La Niña, pues, la selva del amazonas produce el efecto de bomba biótica(Makarieva y Gorshkov, 2007, Makarieva, Gorshkov y Li, 2009).En esta, por su evotranspiración, la cuenca selvática produce un río ascendente, mucho más grande en caudal, que el de su escorrentía en el suelo. La succión de esta bomba biótica está orientada a la masa de aire húmedo del océano Atlántico, que trae consigo el polvo del desierto del Sahara, rico en fósforo, que fertiliza la masa biótica amazónica, como lo evidencia la investigación espacial de la(ScienceAtNASA, 2015).Este fenómeno de la bomba biótica incide directamente sobre las precipitaciones de la cuenca oriental de los Andes colombianos y del piedemonte llanero, como afirman(Bunyard y Herrera, 2012). ...
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Objetivo: Presentar los resultados e impactos de un prototipo de cosecha inteligente de agua lluvia diseñado para la sustitución parcial de agua potable, incluyendo la energía embebida requerida para su producción y distribución, en una vivienda unifamiliar en Bogotá (Colombia). Contexto: La ciudad de Bogotá, posee un régimen bimodal de precipitaciones frecuentes con mínimos mensuales multianuales que superan los 30 mm y como promedio superan los 60 mm. Esta frecuencia de lluvias representa un potencial hídrico y energético, almacenado en la atmósfera, disponible localmente durante la mayor parte del año, de manera que posibilita su realización bajo esquemas novedosos de diseño tecnológico y económico de los sistemas de cosecha de aguas lluvias (SCALL). En este artículo nos centraremos en el establecimiento de las bases de diseño de un prototipo de cosecha de agua lluvia unifamiliar que logre capturar las potencialidades pluviales y energéticas de su entorno y pueda competir eficientemente frente al suministro de agua de la Empresa de Acueducto de Bogotá (EAB). Este permitirá sustituir los usos de agua potable en inodoros, lavado de ropa, riego de jardines y limpieza de espacios y tanques, lo cual se logrará con menor consumo de energía que el proveedor centralizado de agua potable. Método: Se parte de considerar al agua lluvia como un recurso distribuido, tanto de agua como de energía, que tiene la capacidad de sustituir al agua potable provista como servicio energético de abastecimiento centralizado de agua de la EAB. Para evaluar la eficiencia de la sustitución de agua potable por agua lluvia cosechada, se genera un nuevo método que en solo cinco pasos permite evaluar la eficiencia comparativa, tomando como línea de base la proyección del desempeño del servicio centralizado de agua potable, respecto a la medida de mejoramiento del desempeño del prototipo SCALL. Para ello, se toma como principal indicador de desempeño a la intensidad energética comparada; la cual, a su vez, posibilita el cálculo de beneficios múltiples de la eficiencia energética. Resultados: El prototipo SCALL, en las etapas iniciales de su implementación, logró ahorros del agua potable utilizada en la vivienda del 25 %, de la energía embebida del 26 % y el abatimiento de los gases de efecto invernadero en un 27 %. Esto fue obtenido con apenas un 22,4 % de la capacidad nominal de diseño del prototipo, en un periodo de estudio de 56 meses. En este periodo se logró recuperar la inversión a partir de los ahorros económicos producto de la sustitución del agua potable por agua lluvia. Los resultados sugieren que la EAB podría desarrollar un programa de implementación de SCALL eficientes por parte de sus usuarios, lo que le permitiría obtener cerca de un ingresos y ahorros dinerarios que representarían cerca del 2 % del total de ingresos que produciría cada SCALL residencial. El grado de éxito dependería de la masificación del programa. Esto sin contabilizar los beneficios que obtendría al aplazar las inversiones por ampliación de infraestructura, seguridad de abastecimiento y confiabilidad que proporciona la implementación de los SCALL eficientes. Conclusiones: Los resultados de la evaluación de la eficiencia energética arrojan la completa viabilidad tecnológica, económica, ambiental y social del prototipo SCALL de un usuario residencial en Bogotá. A la vez se dispone de una nueva metodología para la evaluación del potencial de eficiencia energética y sus beneficios múltiples cuando es escrutado un servicio energético provisto por un recurso distribuido como es el agua lluvia. Para el Distrito Capital de Bogotá resulta conveniente tanto social y ambientalmente desarrollar una política de promoción del SICCALL como medida de gestión eficiente de la demanda de agua y energía. Esta medida puede ser posibilitada por el desarrollo de economías de red y colaborativas, alrededor de recursos distribuidos de agua y energía, en la vía del cumplimiento de los Objetivos de Desarrollo Sostenible y participación ciudadana, de las llamadas ciudades inteligentes.
... Advances in computer models and the availability of global climate data reinforced a revival of the inquiry into TMR (Brubaker et al., 1993), questioning the extent to which the earth surface, and particularly vegetation, contributes to rainfall patterns via the exchange of mass, energy, and momentum (Bennett & Barton, 2018;Bonan, 2008;Eltahir & Bras, 1996). The biotic pump theory (Makarieva & Gorshkov, 2007) suggests that continental forests are crucial to transport atmospheric moisture of oceanic origin over the continents. These new insights gave rise to the idea that forests influence the climate and generate rainfall. ...
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Green water, or plant-available soil moisture, is a substantial subset of terrestrial fresh water. Land-use change (LUC) alters green water dynamics through interactions on the micro-level (i.e., between the soil and vegetation) and on the macro-level (i.e., between the land surface and atmosphere). Ongoing global deforestation, and growing interest in reforestation projects, begs the question whether such large-scale LUCs have major eco-hydrological impacts via the process of terrestrial moisture recycling. This requires a systematic, mechanistic understanding of green water dynamics in relation to LUC. Hence, this literature review addresses the above question via a scoping review that draws from papers covering empirical observations and simulated approximations on the hydrological effects of LUC from different parts of the world. The results show that some regions are more vulnerable to LUC than others and can affect local as well as distant hydrology of landscapes. Furthermore, we find that many studies focus on the global level or on tropical rainforests, through which we identify a knowledge gap for temperate regions and drylands. We derive analytical tools and directions for further research that can improve understanding of the effects of LUC on moisture recycling patterns to minimize unexpected hydrological impacts for nature and society.
... Forests regulate climate, buffering the effects of extreme temperatures and precipitation, and sustaining the water cycle [22,23]. They filter and purify both surface-and groundwater, and can mitigate floods and droughts. ...
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Forests are the dominant land cover in Nordic–Baltic countries, and forestry, the management of forests for improved ecosystem-service (ES) delivery, is an important contributor to sustainability. Forests and forestry support multiple United Nations Sustainability Goals (UN SDGs) and a number of EU policies, and can address conflicting environmental goals. Forests provide multiple ecosystem services and natural solutions, including wood and fibre production, food, clear and clean water and air, animal and plant habitats, soil formation, aesthetics, and cultural and social services. Carbon sequestered by growing trees is a key factor in the envisaged transition from a fossil-based to a biobased economy. Here, we highlight the possibilities of forest-based solutions to mitigate current and emerging societal challenges. We discuss forestry effects on forest ecosystems, focusing on the optimisation of ES delivery and the fulfilment of UN SDGs while counteracting unwanted effects. In particular, we highlight the trilemma of (i) increasing wood production to substitute raw fossil materials, (ii) increasing forest carbon storage capacity, and (iii) improving forest biodiversity and other ES delivery.
... Studies point to a reliance of the Amazon regional rainfall regimes on the forest [16][17][18] . Although the effects of biome-wide deforestation affecting forest moisture recycling and irreversible biome transition are still relatively uncertain [19][20][21] , at smaller geographical scales, some studies suggest a negative linear response of rainfall to forest loss [22][23][24] , while others indicate a nonlinear response 2,[25][26][27] . ...
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It has been suggested that rainfall in the Amazon decreases if forest loss exceeds some threshold, but the specific value of this threshold remains uncertain. Here, we investigate the relationship between historical deforestation and rainfall at different geographical scales across the Southern Brazilian Amazon (SBA). We also assess impacts of deforestation policy scenarios on the region’s agriculture. Forest loss of up to 55–60% within 28 km grid cells enhances rainfall, but further deforestation reduces rainfall precipitously. This threshold is lower at larger scales (45–50% at 56 km and 25–30% at 112 km grid cells), while rainfall decreases linearly within 224 km grid cells. Widespread deforestation results in a hydrological and economic negative-sum game, because lower rainfall and agricultural productivity at larger scales outdo local gains. Under a weak governance scenario, SBA may lose 56% of its forests by 2050. Reducing deforestation prevents agricultural losses in SBA up to US$ 1 billion annually. Deforestation in the Amazon region has suggested to influence precipitation in a non-linear way. Here, the authors show that forest loss is associated with decreasing precipitation after a scale-dependent threshold is crossed, which can cause stress on agriculture if deforestation is expanded.
... Bonan found low albedo as a positive climate forcing of boreal forests and tropical forests reduce warming through evaporation. Makarieva and Gorshkov [3] have studied the relation between moisture and runoff water after precipitation and presented a simple basic concept of how the forests help in precipitation. Sheil and Murdiyarso [4] have supported the idea of Makarieva and Gorshkov to motivate forest conservation. ...
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