Half of the World's Annual Precipitation Falls in Just 12 Days, New Study Finds
Published on by Water Network Research, Official research team of The Water Network in Case Studies
Climate change likely to make global precipitation more uneven.
By Laura Snider
Weather station on Mount Vesuvius (Image source: Michal Osmenda, Wikimedia, labeled for reuse)
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Currently, half of the world's measured precipitation that falls in a year falls in just 12 days, according to a new analysis of data collected at weather stations across the globe.
By century's end, climate models project that this lopsided distribution of rain and snow is likely to become even more skewed, with half of the annual precipitation falling in 11 days.
These results are published in Geophysical Research Letter s, a journal of the American Geophysical Union.
Previous studies have shown that we can expect both an increase in extreme weather events and a smaller increase in average annual precipitation in the future as the climate warms, but researchers are still exploring the relationship between those two trends.
"This study shows how those two pieces fit together," said Angeline Pendergrass, a scientist at the National Center for Atmospheric Research (NCAR) and the lead author of the new study. "What we found is that the expected increases happen when it's already the wettest — the rainiest days get rainier."
The findings, which suggest that flooding and the damage associated with it could also increase, have implications for water managers, urban planners, and emergency responders. The research results are also a concern for agriculture, which is more productive when rainfall is spread more evenly over the growing season.
The research was supported by the U.S. Department of Energy and the National Science Foundation, which is NCAR's sponsor.
An analysis of rainfall measured at weather stations across the globe between 1999 and 2014 found that the median time it took for half of a year’s precipitation to fall was just 12 days. A quarter of annual precipitation fell in just six days, and three-quarters fell in 27 days. (Image Source: Simmi Sinha, UCAR, labeled as freely available for media & nonprofit use)
What it means to be extreme
Scientists who study extreme precipitation — and how such events may change in the future — have used a variety of metrics to define what qualifies as "extreme." Pendergrass noticed that in some cases the definitions were so broad that extreme precipitation events actually included the bulk of all precipitation.
In those instances, "extreme precipitation" and "average precipitation" became essentially the same thing, making it difficult for scientists to understand from existing studies how the two would change independently as the climate warms.
Other research teams have also been grappling with this problem. For example, a recent paper tried to quantify the unevenness of precipitation by adapting the Gini coefficient, a statistical tool often used to quantify income inequality, to instead look at the distribution of rainfall.
Pendergrass wanted to find something even simpler and more intuitive that could be easily understood by both the public and other scientists. In the end, she chose to quantify the number of days it would take for half of a year's precipitation to fall. The results surprised her.
"I would have guessed the number would be larger — perhaps a month," she said. "But when we looked at the median, or midpoint, from all the available observation stations, the number was just 12 days."
For the analysis, Pendergrass worked with Reto Knutti, of the Institute for Atmospheric and Climate Science in Zurich, Switzerland. They used data from 185 ground stations for the 16 years from 1999 through 2014, a period when measurements could be validated against data from the Tropical Rainfall Measuring Mission (TRMM) satellite. While the stations were dispersed globally, the majority were in North America, Eurasia, and Australia.
To look forward, the scientists used simulations from 36 of the world's leading climate models that had data for daily precipitation. Then they pinpointed what the climate model projections for the last 16 years of this century would translate to for the individual observation stations.
They found that total annual precipitation at the observation stations increased slightly in the model runs, but the additional precipitation did not fall evenly. Instead, half of the extra rain and snow fell over just six days.
This contributed to total precipitation also falling more unevenly than it does today, with half of a year's total precipitation falling in just 11 days by 2100, compared to 12 in the current climate.
"While climate models generally project just a small increase in rain in general, we find this increase comes as a handful of events with much more rain and, therefore, could result in more negative impacts, including flooding," Pendergrass said. "We need to take this into account when we think about how to prepare for the future."
Reference: "The uneven nature of daily precipitation and its change" by Angeline G. Pendergrass and Reto Knutti, Geophysical Research Letters
Source: UCAR & NCAR News
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Not “climate change can make global precipitation more uneven.” But, conversely, global precipitation changes the climate
The direct executor of all natural disasters is water - the main product, carrier, means and condition for the existence of life on the planet. Water accumulates in the clouds, moves, precipitates, dissolves minerals and organic matter in itself, delivers it to animals and plants that process these substances in their life. And the liquid, after numerous transformations in food chains, returns to the atmosphere. Each type of plant and a living organism, and within each species, each individual has his own personal properties of consumption, their own mechanisms for the transformation of water and the removal of waste moisture from his body. One of the main properties of water is that it does not disappear, but participates in the construction and functioning of organisms and changes itself. Entering into an organism with one structure, introduces solutes, is repeatedly transformed into blood, flesh, plasma and leaves with another structure. All waste in the form of exhalation, various juices, secretions, transpiration of plants have their own specific individual properties. This is how we feel the fragrance of flowers when inhaled; animals smell their victims and partners by smell. Expiratory and urine medics diagnose diseases. Water, as a conductor of substances, is a means of processing, in the process of vital activity enters the body with a certain solution and comes out in the same quantity, but in a different quality.
All the diversity of evaporation from biota somehow participates in atmospheric phenomena, and more precisely in the water circuit on Earth, corresponds to the volume of all living things and was created from the moment of origin of life on the planet. In symbiosis of biota and water, the relief of the planet's surface was created, a schedule of water distribution was established — the amount, time and place of precipitation; various arid zones were formed in terms of precipitation volumes and periods — deserts and tropics, forests and savannahs.
The full cycle of water transformation contains part of the path through food chains and the release of moisture and waste products of the animal and plant worlds. It is this part of the path that destroys humanity. Evaporation with the development of the industry, began to change in quality, quantity and speed.
Man, with the development of industry and his own comfort, began to use water not only and not so much for drinking, but for needs not provided for by nature. Water has become a means, a working fluid, a reagent in a variety of technological processes. These are washing, cooling, boiling, transportation, energy production, watering of plantings and many other uses in the production of agriculture and communal processes, after which the water evaporates directly and after discharge into the sewers and rivers. As a result of the development of civilization, humanity is increasing its water consumption for these purposes at an increasing rate. Almost all waters taken from nature by man have lost their natural purpose. The natural mechanism of atmospheric phenomena broke. Precipitation began to fall out not in established regions, in periods not set by nature, and in increased volumes. This is confirmed by recent studies:
“At present, according to a new analysis of data collected at meteorological stations around the world, half of the precipitation a year falls in just 12 days.
By the end of the century, climate models predict that this one-sided distribution of rain and snow is likely to become even more asymmetric, and half of the annual precipitation will fall in 11 days.
These results were published in a geophysical research letter from the Journal of the American Geophysical Union. ": Https://thewaternetwork.com/_/climate-change-and-the-environment/article-FfV/half-of-the-worlds- annual- precipitation-falls-in-just-12-days-new-study-finds-wOcamCYuSZaC81N9KQ7rug
At present, the water cycle on the Earth’s surface consists of 520,000 km3 of water. At the same time, 109,000 km3 a year falls on the continents, and 72,000 km3 or 72 trillion tons evaporates, the rest flows into the seas and oceans [1].
The officially accepted hypothesis of climate change found the culprit - carbon dioxide. According to UN experts, “the increase in CO2 emissions ranged from 0.5 to 5% per year. As a result, over the past hundred years, only 400 billion tons of carbon dioxide has been released to the atmosphere due to the combustion of fuel ”[2]. On average over a hundred years - 4 billion tons per year.
72 trillion divide by 4 billion, we get 18,000. It is eighteen thousand times the evaporation exceeds carbon dioxide in terms of volumes lifted into the atmosphere for 1 year. In other words: the atmosphere accepts 1 part of CO2 and 18000 parts of water vapor. Only from this alone, it can be concluded that the effects on climate and weather produce more water evaporation, and not CO2. Each of us feels this on an overcast day.
According to [3], annually mankind extracts up to 20 thousand cubic kilometers of groundwater for its needs. Plus to this, according to [4] people irrevocably take away from pek and lakes approximately 2 thousand cubic kilometers of fresh water. Annually. All this water through pipes and channels goes into another redistribution. This is an unnatural use of water for nature - agriculture and public utilities, industry, water supply networks. Washing sewage into the sewage system, water solutions of a wide variety of chemical and biological substances - from household chemicals to residues of petroleum products during washing, to pesticides from the fields. Sewage is drained to septic tanks and rivers. Water molecules react with molecules of a multitude of chemicals and organics, and, for sure, they take something into the atmosphere when they evaporate. Such an assumption can be made if we take into account the appearance of acid rain. Maybe they do not capture, but their own quality, structure is not the same as that of vapor molecules exhaled by biota. Evaporation from drying washed things - dishes, linen, asphalt, from coolers and evaporators of many factories, from the surfaces of sumps, nature is not provided. To this should be added significant amounts of evaporation that bypass biota consumption - these are huge territories of arable land, landfills, water reservoirs, areas of deforested forests and asphalted cities and roads, and water areas of flooded areas. All such evaporations can be safely called artificial evaporations. Research on the quality of evaporation from biota and artificial evaporation was not found. This is just an assumption, a hypothesis and, as each hypothesis, needs proof. Studying the issue is quite simple, but it is very important - it determines the differences between organic and artificial fumes, and can provide the basis for the conclusions of the role of water in climate change. And a real means of preserving and restoring climate.
Without focusing on the quality of evaporation, it is necessary to pay attention to the quantitative and temporal parameters of evaporation. It is assumed that the entire volume of artificial evaporation from only water and irrigation water alone is 22,000 cubic meters. kilometers or 22 trillion cubic meters. tons of water and this volume takes up more than 1/3 of the total evaporation of 72 cu. kilometers of all fumes. To these should be added and the total evaporation from degraded areas - landfills, arable land, reservoirs. The precipitation they do not find their natural consumers and evaporate without structural changes - what came, then went. Significant amounts of destruction of water molecules occur directly in the air by a variety of internal combustion engines and all furnaces and heaters. Each volume of atmospheric air contains water in a molecular state. When it gets into the burner of the furnace or the combustion chamber in the cylinders of engines, compressors, this moisture does not burn, does not disappear. It changes its structure and joins artificial evaporation.
Artificial evaporation has become not just commensurate with organic evaporation, but reached a critical state in terms of volume and time of return after precipitation. The mechanism of natural transformations broke down in the troposphere. Nature had no such amount of evaporation before, before the development of civilization. There was a transition from quantity to quality. Unbelievably new volumes for nature have led to a new mechanism of action in the troposphere — natural disasters and climate change have begun. The growth of artificial vapors continues with the development of industry and our comfort. Moreover, this growth has a rather strong acceleration, as industrial and utility technologies develop and expand, increasing productivity in agriculture, mining, construction of cities and roads, and hydroelectric power plants with water accumulation in reservoirs.
All these evaporations have a speed greater than natural evaporation. In the soil, water spreads and is consumed by plant roots, microbes, worms, and exhaled over time, in accordance with the properties of plants or living organisms. Each accepted portion of water passes through all the stages of organic transformations of the body and leaves after a few days with vapor of breathing and transpiration of the plant. The water, which stood in a puddle on asphalt or heated in a kettle, leaves instantly in a few minutes. Consequently, artificial evaporation returns to the atmosphere much faster, and dense clouds hang over us almost continuously. We have rarely felt sunny days. Heavy clouds may not rise above mountain glaciers, do not replenish ice reserves. Do not overcome the path to the polar glaciers.
This is one of the factors by which the weather anomaly is observed. The second factor comes from the analysis of natural disasters. There are areas of the planet where there is unprecedented rainfall, leading to flooding. And vice versa, areas that are not precipitated for a long time - there are fires. Anomalous sediments began to appear there, de them never had been - in the deserts. The third factor is the rise in the level of the oceans. The loss of stability in the distribution of precipitation by geography gives the right to think that the burdened clouds do not reach the polarand mountain glaciers and precipitations en route. The natural growth of glaciers is decreasing, and precipitation in other places replenishes rivers and oceans.
Thus, the quality, volume and speed of artificial evaporation broke the mechanism of water circulation valid for millions of years and lead to a global catastrophe.
If we want to leave our descendants a normal climate, then we must now begin to return nature to its organic evaporation and reduce artificial. To accomplish this, it is necessary to develop a new concept based on the proposed hypothesis. The main focus of the concept should be the reduction of artificial vapors. Here are a few of these elements.
The most wasteful evaporator is agriculture. Up to 9% of all fumes accounts for his case. Deep plowing of fields destroys underground living creatures - 20 tons of it per hectare. Every organism, every stalk of this living creature has its own water circuit. Dead arable land, without recycling water, returns it back to the atmosphere unchanged. Especially a lot of water is consumed in growing rice and cotton. About 1,350 billion m3 of water is consumed annually in the rice fields of the world — 21% of the total water consumption for growing crops [5]. "... global cotton production in the amount of 18 million tons per year implies the transfer of 100 billion tons of water" - [6]. In the concept it is necessary to set tasks for replacing these products with others. For example, it is known that clothing can be made from wood, from artificial fibers. More important is the development of ways to reduce water consumption during cultivation. Barbaric irrigation methods based on irrigation systems, sprinklers are used. Although drip irrigation methods have long been known and used. For example, in Israel and the United Arab Emirates. It is necessary to fully switch to these measures.
Among the most destructive human activities on Earth in its relationship with water is hydropower. Developing alternative energy, we are building and launching new hydroelectric power plants. They, from their reservoirs, raise into the sky new artificial vapors that harm the climate more than they give the benefit to man. Known non-pressure diversion hydroelectric. They are effective in mountainous areas, but such inventions are also known for plain places. With the possibility of using existing hydroelectric power plants with the release of reservoirs. In general, everything that concerns the accumulation of water, river turns, flooding of new territories is directed against nature. We must leave the existing rivers alone. At the same time, all the problems of transboundary rivers will be removed.
A significant proportion of artificial evaporation occurs from flooding of coastal areas of rivers with flood waters. Rivers in constant motion wash off coastal particles and build up their bottom. Intense human economic activity complements this process with its garbage. Increasing the bottom leads to an increase in the level of rivers and, with heavy rainfall, to the release of water from the banks. An urgent deepening of the river bottom is needed to eliminate flooding.
We spend very large volumes of water in everyday life. In this area it is necessary to revise all plumbing devices to reduce water consumption. For example, means are known for saving water by simple washing. We use this in aircraft and railcar toilets.
There are a lot of such moments and take it over everything. A total saving of water consumption is needed in every enterprise, in every apartment, by all countries, by each person.
[1] http://ru-ecology.info/page/00307874802712200330005000049688/
[2] http://www.refsru.com/referat-17732-3.html
[3] http://jkg-portal.com.ua/ru/publication/one/globalna-posuha-abo-problemi-vodospozhivannja-32688
[5] http://ecology.md/page/rashod-vody-na-proizvodstvo-produkto
[6] https://studopedia.ru/12_86797_proizvodstvo-hlopka-pri-umenshennom-rashode-vodi.html
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КЛИМАТ МЕНЯЕТ НЕ КАРБОН, А ИСПАРЕНИЯ
Миллионы лет формировался кругооборот воды между атмосферой и почвой, строилось динамическое равновесие. Определенное количество испарений с земли создавало такой механизм атмосферных явлений, который направлял воду облаками в заданные места планеты. Так образовались различные аридные зоны - степи, пустыни, тропики, леса.
Цивилизация превратила воду в рабочий реагент. Вода стала основным действующим телом во многих производственных и коммунальных процессах - носителем тепла, энергии, средством охлаждения, закалки, мойки, стирки, влажной уборки всего, что нас окружает. Все непосредственные испарения с этих процессов и испарений после канализации использованной воды неестественны, назовем их искусственными. Природный путь воды – это ее движение и преобразования в пищевых цепочках в почве и на почве через биоту - микробы, черви, растения, животные. В каждом из них вода проходит многочисленные преобразования и в виде выдоха, транспирации, соков и других выделений вновь превращается в парообразное состояние. Все эти органические испарения объединяется в атмосфере, и создают свой, уникальный механизм образования облаков, который совершенствовался до появления человека. Мы уничтожили более 60% этой идиллии – почвы и обитающей на ней живности с растениями, создав пашни, водохранилища, свалки, асфальт, бетон.
Объемы и скорость искусственных испарений нарастают с увеличивающимся ускорением в соответствии с развитием технологий. Приближаясь к своим предельным значениям, они начали превышать органические по качеству, объемам и скорости оборота. Сломался механизм формирования атмосферных явлений. Мегатонны воды нового качества стали проливаться осадками не в заданных природой местах, не в заданных объемах, не в заданное время, а по другим - неведомым природе законам и правилам. Количество переходит в качество. Именно поэтому в одних местах превышения осадков с наводнениями, в других - засуха и пожары. Рушатся аридные зоны, исчезают виды растений и животных, повышается уровень океанов – вода облаками не доходят до полярных и горных ледников, выпадая в пути следования. Не пополняются ледники – разрушается вековечный процесс преобразования, хранения и обновления воды. Исчезают ледники, меняется планета.
Все усилия человечества, направляемые Парижскими соглашениями, ведут к катастрофе, потому что не углерод воздействует на атмосферу, а испарения. Затрачивая средства на микроскопическое воздействие – снижение эмиссии СО2, мы не обращаем внимания на главный, источник стихийных бедствий, разрушитель климата.
По оценкам экспертов ООН, [12], «увеличение выбросов СО2 составляло от 0,5 до 5% в год. В результате, за последние сто лет только за счет сжигания топлива в атмосферу поступило 400 млрд. тонн углекислого газа». Или 4 млрд. тонн в год.
По данным [13], ежегодно человечеством для своих потребностей извлекается до 20 тыс. кубических километров подземных вод. Плюс к этому, по [14] люди безвозвратно забирают из рек и озер приблизительно 2 тыс. кубических километров пресной воды. Ежегодно. Почти вся эта вода извлекается из природного оборота, используется в земледелии, промышленности, коммунальном хозяйстве и через канализацию и испарения уходит в атмосферу без органических изменений. 22000 куб. километров – это 22 триллиона куб. метров или тонн воды. В составе испарений эмиссия 4 миллиарда тонн СО2 – это всего лишь 0,018 % - незаметная капля. Может ли эта капля, которая в 5500 раз меньше одних только искусственных испарений на что-то воздействовать? Соотношение можно смело удвоить, если добавить и органические испарения, с сохранившейся половины суши в природном состоянии.
Одним из элементов Парижского соглашения является сокращение сжигания всех видов топлива и переход к альтернативным источникам энергии. В числе этих источниеов апедусматриваются гидроэлектростанции. Например, в Китае по данным:
https://www.dw.com/en/china-to-invest-360-bln-in-renewable-power-in-2016-2020/a-37031957 :
500 миллиардов юаней пойдет на гидроэнергетику. Гидроэнергетика - это гидроэлектростанции. Достраивается самая мощная в мире ГЭС «Три ущелья», следом еще несколько проектов. Затапливаются тысячи гектаров плодородных земель водохранилищами. Новые ГЭС планируются и во многих других странах. Например, Рогунская в Таджикистане. Это новые искусственные испарения. Снижая на тысячные доли процента эмиссию СО2, мы на десятки процентов повышаем искусственные и снижаем органические испарения
Еще большие территории, 9% всей суши, мы распахали под земледелие глубокой вспашкой: https://ru.wikipedia.org/wiki/Пашня. Вода осадками, выпадающая на пашню не находит подземных природных обитателей и без изменений сразу уходит обратно в атмосферу.
Большие территории мы заваливаем мусором и отвалами горнорудной промышленности. Под многометровыми слоями таких отвалов вымирает подземная жизнь, исчезают органические испарения.
Площадь мирового леса уменьшилась до 30 %. Деревья испаряют чисто органические пары. Гектар подмосковного леса испаряет за лето через листья до 44 тонн воды. Это значит, что из почвы растения впитывают влаги намного больше. Всего же растения планеты за год поглощают 650 триллионов воды, причём рекордсмены — тропические леса. Подсчитано, что за миллион лет растения планеты были бы способны иссушить все моря и океаны. - http://sitekid.ru/biologiya/interesnye_fakty_o_rasteniyah/skolko_vody_potreblyayut_derevya.html
Всего в мире опустыниванию подвержено более 3 млрд. га земель – [9] – это 30 млн. км2 или 20 % от всей суши - 149 млн. км2. По другим данным – 63%. В любом случае стали соизмеримыми с общей территорией и продолжают нарастать.
Если мы хотим спасти жизнь нашим потомкам и вообще жизнь на планете, мы должны принять новую концепцию возвращения воде ее природных функций.
Научное доказательство этой гипотезы достаточно несложно и лежит на поверхности. Необходимы сторонники и специалисты, организующие исследование солидными силами.
Более подробно: http://ethnopharmacology-asia.com/index.php?page=Abstract&Abstractid=MTA3