Last winter, many European regions were snow-free. Long-awaited in Wrocław, it came just for a moment on the last day of March. In the early morning, the university’s meteorological observatory registered 2-cm-high snow surface, which was gone by noon. The city enjoyed sunny weather for the next couple of weeks. Next rainfall (0,6 mm per square meter) came on 25th April and it was one of few in recent months. This paper, however, is not a weather report but rather it describes an environmental and economic problem that is being increasingly often discussed – drought.
Drought can be defined differently depending on climate zone. By and large, it is a period of time without or with lower-than-average amount of precipitation. In some African regions, drought appears after two rainless years. This period is six days in Bali, Indonesia, and twenty days in Poland. There are three main stages of drought. Lack of precipitation is atmospheric drought. When there is not enough water for plants, we have soil drought. When the level of surface and ground water is lower, we are talking about hydrological drought. When this state lasts for a longer period of time, it may lead to hydrogeological drought.
Drought over years
Deficit of water is an ongoing but not at all new problem. Historical report on drought in Poland prove that the main factor causing that sort of situations are weather and climate conditions. Chronicles from previous centuries explicitly show how drastically droughts affected this part of Europe. These descriptions are being studied by many historians. In 1932 in Lviv, Antoni Walawender published “Chronicles of elementary diseases in Poland and neighbour countries.” In 1986, S. Inglot also gathered information from historical sources about the Silesian district. Recently, our university’s researchers under management of E. Kościk took part in an extensive project on reports of occurrences of extreme natural phenomenon in Poland. Authors based their analysis on drought report from the 10th century, so over a thousand years back in time, mostly gathered by Jan Długosz. What sort of information is it? Summer 1473 – “heat and lack of water. Places where there was always water are now completely dry, and Polish main rivers could be crossed anywhere.” 1540 – “a year of a great drought, from 24 June there were no rainfalls for six months, rivers dried out, Oder could be crossed with a cart.” 1590 – “In Silesia, Bóbr, Kwisa, Kaczawa, Widawa, Oława and other smaller rivers dried out.” 1590 – “there has been no rain for 38 weeks,” etc. Of course, information in chronicles is not precise and it is limited to certain regions, mainly Silesia, Pomerania, and Lesser Poland. Accounts from more recent times are no different. In 1811 the level of water in Oder was so low that the river could be crossed by foot or cart. In August 2015, we observed with apprehension how the Vistula’s riverbed in Warsaw was more and more exposed.
Instrumental measurements provide more detailed data on meteorological-hydrological situations. However, they started to be used regularly from the 18th century. The oldest series of measurements was taken in Gdansk. Christoph Hanow, rector, professor of mathematics, historian and meteorologist, conducted daily rainfall observations. The results were published weakly in ‘Danziger Erfahrungen’ paper. The longest-lasting series of such observations began in 1791 in Wrocław. A year later, similar observations started in Cracow. Today, it is also possible to reconstruct earlier environmental conditions with the use of dendrochronology. Unfavourable conditions, such as droughts, take their toll on the yearly tree growth. Through calibrating the annual growth of tree trunks in modern times, it can be estimated how trees reacted to the environmental conditions, and thus how weather changed centuries earlier. Not only are growing trees the subject of study but so is timber used in historic buildings.
Recently, a prestigious paper ‘Climate of the Past’ published an article in which Professor R. Przybylak from the Nicolas Copernicus University in Toruń, together with his associates put together data gathered from chronicles, results of instrumental measurement series and dendrochronological reconstructions from the 996-2015 period. According to them, there were more than 100 droughts in Poland between the mid-15th to the end of 18th century. 17 of them were regarded as megadroughts as they were extremely catastrophic. Between 1722 and 2015, the greatest number of droughts lasted for two months (60%-70%), some for 3-4 months (10%-20%), and some 7-8 months. Authors emphasize that, usually, droughts happen during winter. This fact needs to be taken under consideration when analysing historical sources, which most often focus on the deficit of rainfalls during the period of plants vegetation.
Are we going to experience megadrought?
Since the second half of the 20th century, droughts affecting at least 75% of Poland appeared in the following years: 1951, 1959, 1969, 1982, 1983, 1984, 1989, 1991, 1992, 1993, 1994, 2000, 2002, 2003, 2005, 2006, 2011, 2015, 2018, 2019. In 1969, it covered 95% of the country. This data suggests that drought in Poland is not an unusual phenomenon. However, lack of catastrophic droughts in the past two centuries makes us neglect the seriousness of the problem. A reappearance of mega-drought would mean a massive economic crisis. Today, even weaker droughts greatly affect many people. Analysing the data published by the Polish Institute of Meteorology and Water Management (IMGW), it can be seen that last year Central Poland had only 300-400mm of rainfalls, much below the average from previous years (600mm). For the Greater Poland region, such low numbers mean diminished effectivity of harvest. Farmers do not remain idle and, as an alternative to lack of rain, they exploit ground water more intensively. As Jan Krzysztof Ardanowski, the Minister of Agriculture and Rural Development states, “340 thousands of farmers registered loss as a result of drought in 2019.”
Another important phenomenon that cannot be unnoticed is little or, in some areas, total lack of snowfalls. Snow surface should guarantee effective and sustained irrigation of the soil and restoring ground water reserves. Rapid climate change that has been observed in recent decades, leads to unfavourable changes in Polish water balance. Water supply from the atmosphere is being disposed unequally throughout the year. Dry periods are interspersed with high-volume rainfalls. Surplus of water quickly drains off because the upper levels of soil have dried and, thus, this changed structure inhibits water absorption.
Fight against drought
Last weeks’ events prove that we are not yet prepared for the battle with drought. That might result from the fact that we are still losing natural shelter. By this I mean the balance of waters that has changed significantly in the past 200 years. Drying wetlands, land reclamation, straightening and building concrete riverbeds, building levees ridiculously close to streambeds, water evaporation from reservoirs, redevelopment of forests for the needs of farmers, degradation of old-growth forests, undergrowth and groundcover, cutting trees and shrubs growing in the middle of a field, dense network of mountain roads and tracks that drain rainwater, dewatering mining fields, or hardening big areas in towns (shopping centres’ car parks) – those are just some of the human activities that affect natural retention badly. Disturbing images of dust blizzards (like the Dust Bowl* in the USA) taken by farmers from the Lublin Region, depict great acreages of soil that is exposed to wind erosion. Was land consolidation and cutting all the trees and shrubs really worthwhile? The assumptions of most of these activities were established in different climate reality. One might say that many of the investments within water resource management from the past match the reality of the Little Ice Age (lasting until 1850) but not the modern trends.
There is no recipe for improvement of water situation in our country because any proposition will cause conflict of interest. The first step should be education and reliable information jointly devised by experts in different fields. In today’s reality, it would be worth ending all the political and social disputes and focusing on the improvement of water situation. Necessary are solutions that stimulate many different areas of the economy, especially agriculture and forestry. Sources of the problem of insufficient natural water retention should be searched for in primarily these two areas. Particularly wetlands, river valleys and spring areas should be taken care of.
Small retention – big support
Experience from many places in the world proves that small retention is very effective and in line with, so called, ‘blue infrastructure.’ Brad Lancaster (1967) became an icon in this current. Living in Tucson in Arizona, he struggled with unfavourable conditions of the local, desert climate with 294mm of rain a year and the temperature in July reaching 40°C (the highest temperature of 47,2°C was recorded in 1990). Tucson is a city plagued by rapid floods. Human errors that are difficult to reverse, such as cutting gallery forests at the bottom of valleys and excessive exploitation of ground waters by farmers, the Santa Cruz’s riverbed dries out. In these conditions of permanent drought interrupted by sudden floods, Brad Lancaster came up with an initiative to manage rain water. He was inspired by Zepbaniana Phiri Maseko (1927-2015) who filled degraded areas in Zimbabwe with trees, revitalizing thereby river system. In his garden, Lancaster started gathering water from street by making hollows and planting plants in such a way that the water was draining in a pre-planned direction. Thanks to his enthusiasm and charisma, his neighbours started copying his ideas. Some of their measures were illegal, for instance removing high kerbs. Soon, the area became green without costly irrigation and their measures were accepted by the local government. This process was called ‘plant the rain.’
Although in Poland the climate is more favourable than in Tucson, problems connected with surplus of rain water or snowmelt, as well as with drought in summer are equally important. What is more, literature clearly indicates that the solutions are available and ready to use. What is lacking, however, is the belief that they are necessary. For architectures and designers, one of the challenges is planning urban development that is based on ‘Low Impact Development’ and ‘Water Sensitive Urban Design’ concepts. The first concept tells how to adjust cities to the natural character of the environment and preserving its advantages. The latter one assumes that green areas take as much of the territory as possible. Now, let us look at Wrocław from this perspective.
Unfortunately, measures that are being currently put in place are interim. Farmers try to save harvest productivity by building irrigation systems and drilling wells. The deficit of rainfalls prompts farmers to drilling wells on a broad scale. Existence of too many wells in a little area often leads to social disputes, in which farmers accuse each other of predatorily exploiting groundwater. According to GUS (Central Statistical Office), we are exploiting 1777 thousand m³ of groundwater a year, which is 5.5 times less than surface water. According to the Polish Geological Institute reports from 2019, despite increased exploitation of groundwater, its decline was not recorded in any Polish voivodeship. However, there was observed incremental depletion of groundwater as a result of deficit of rainfalls in 2018 and 2019.
Poland like Egypt?
Drought is a great opportunity for spreading certain inaccurate information. One of them is comparing water resources in Poland to those in Egypt. It is being widely disseminated in the media, by politicians, or even on Wikipedia. Although this comparison has been criticised multiple times, it serves as a catchy slogan. Why is it wrong? Reports from the Food and Agriculture Organization of the United Nations (FAO) explicitly show that renewable resources of surface water are similar to resources in Poland (56 vs 60 billion m³ a year) but the fact that groundwater is unfavourable for Egypt (1.5 vs 12.5 billion m³ a year) is often ignored. It is worth noticing that this data does not take into consideration the fact that Egypt is three times as big as Poland. In order to comprehend the absurd of this comparison, it needs to be understood that the dominating part of surface water in Egypt belongs to Nile, whose basin’s surface reaches nearly 3 million square kilometres, mostly outside of Egypt, whereas the surface of Poland is almost ten times smaller. Another fact that is often ignored is estimating water resources per capita. Egypt is a country with more than 100 million inhabitants. Also, it is different climate zone, river structure and land development, thus the comparison is pointless.
It does not mean, however, that Poland’s water resources are sufficient. According to FAO, Poland belongs to the group with a deficit of water (Egypt is a country with chronic shortage of water). In comparison with the European average, we look bad. Data from Eurostat show that in Poland, there is 1566m³ of water per capita, 4560m³ in Europe and only 589m³ in Egypt. The reason for this lays in the sum of precipitation (on average 600mm), fast draining, relatively big loss of water due to evaporation, and bad retentiveness of the geological substratum.
Another slogan that is being often used refers to steppe-formation of our country. This outlook was formed in Germany and quickly became widely propagated in Poland by Professor Adam Wodziczko from the University in Poznań. Although his observations on the hydrographic conditions as a result of human activity were true, he was mistaken about the drastic changes of hydrological situation. Measurements prove that the processes that he observed did not have much to do with steppe-formation. Steppe-formation processes include gradual appearance of xerophytic plants characteristic for semiarid zones, as well as transition of meadows, pastures and brush into grasslands similar to those in dry climate. Poland is located in moderate climate and forests are still its natural habitats. It needs to be emphasized here that their condition is not good, just like the condition of the whole of animate nature. Biologists are warning – biodiversity drastically decreases. In scientific literature, it is stated that we are on the cusp of the sixth mass extinction. It is not surprise, as our ecumene covers over 90% of landmass and we are exploiting ocean resources immoderately.
What to do?
What should we then do in the face of drought? Save water? Considering the need for irrigating crops, saving water seems to be a difficult endeavour. The biggest consumer of water is industry (mainly energetic and mining), though it consumes gradually less water due to the development of technological development. For sure, we cannot let ourselves waste it. Water retention is a real challenge. Slowing down water draining and evaporation, as well as water retention – these are plans that are feasible, starting in our own gardens. Small water retention measures need to be implemented on a broad scale – in forests, farmlands, and urban areas. Foresters and farmers are doomed to it because their crops are already in trouble. In forests, decreased dampness results in pest outbreak, loss of some species of trees, prolonged desiccation of forest cover and fire hazard. Blue or blue-green infrastructure solutions will help inhabitants of urban areas cope with hot summer temperatures.
The ‘Plan of counteracting consequences of drought in drainage areas’ programme aims at improving the current situation. Let us hope that the solutions will not be about refurbishing old-fashioned projects for which there was insufficient budget but rather that they will recommend devising innovative ideas, including demolition of the existing infrastructure that is harmful in terms of current needs of water economy. Important are local and widespread actions that sometimes require only an update of regulations. Unfortunately, country’s policies of water economy are full of contradictions. Politicians and authorities should not mislead the public with false information about nature condition and natural processes. Fake news is one of the greatest dangers today. We all need to understand that the state of the environment depends not only on politicians but also on each one of us.
*Dust Bowl (1931-1938) – period of a great ecological disaster that affected 19 states within the Great Plains. The disaster was caused by drought and soil erosion. Exposed and dry ground brought about dust floating in the air, appearance of dusters, decrease of crops, farmers suffering from pneumoconiosis or suffocating. The greatest storm, rushing from Oklahoma to Canada, happened on 14 April 1935, a day that was called ‘Black Sunday.’ Dust Bowl (or ‘Dirty Thirties’) coincided with the period of Great Depression in America. The situation was under control after having signed the act on the protection of agricultural lands by the Congress.
Dr Marek Kasprzak, Anna Salamon, Institute of Geography and Regional Development
Authors would like to thank Professor Krzysztof Migała for valuable comments.