9
Introduction
This research thesis investigates drought as a local and international phenomenon,
analyzing the Liguria region and its repercussions in 2022/2023 at an environmental but also
governance level. Drought today, moreover, is a phenomenon that is increasing in
frequency and intensity which, seen globally, is the generative cause of numerous internal
conflicts which will grow increasingly due to the projections on climate change. The choice
of this topic is motivated by the desire to investigate the causes of this phenomenon which
is manifesting itself in an increasingly systematic way in different areas of the world and to
understand what the viable solutions and the negative implications for the environment
are. This work discusses how we are about to interface with one of the greatest
environmental security risks that we will not be able to predict or control, capable of long-
term disastrous effects and affecting the most valuable resource for life on planet Earth:
water. Despite being a very frequent phenomenon worldwide, there does not seem to be
sufficient attention to it particularly in countries traditionally not affected by droughts such
as temperate countries. This is the case of Liguria, a region characterized by a temperate and
rainy climate which since early 2022 has been experiencing an incredibly significant
drought, just like most of Italy and Europe. The main aim of this research is to analyse the
drought in terms of its climatological and environmental manifestations, as well as for the
implications at social and governance levels. The research consists of the analysis of the
phenomenon through the analysis of meteorological and hydrogeological data and the
methodology of semi-structured interviews
1
with various stakeholders involved in water
management. The research methodology entailed a careful analysis of data, unveiling the
urgency of a prompt intervention aimed at mitigating the effects of what already is current
issue institutions must face and providing evidence that it is the moment to act at the various
political, diplomatic, and institutional levels to implement prevention actions that can
introduce innovations in terms of sustainability, prevention, and savings. The strong point
1
R. Longhurst, (2003), Semi-structured interviews and Focus Groups,
https://www.researchgate.net/publication/268036642, [Last Accessed 20/06/2023].
10
is precisely this: understanding that, given the current critical situation and forecast,
institutions have the duty and the burden to burden too obvious deductions that no longer
represent probabilistic hypotheses far from the reality, but facts now consolidated in the
daily life of each of us and it is exactly there that the change starts, from our small actions
up to the point of requesting a joint global effort. The present paper here is therefore divided
as follows, presenting a careful inspection of world data and trying to identify the areas
currently most at risk, notably Sub-Saharan Africa, a land of long-lasting droughts and
conflicts. The first chapter examines the situation in the Liguria region which has been
undergoing water shortage, a situation which does not seem to be improving even in winter.
The last part focuses on personal communication provided by experts and local
administrators and meetings that took place with the experts in question who have kindly
released the permission to be mentioned and reported in this research, including the actions
put in place by the political class which, as has already happened for scholars and scientists,
is realizing that intervention as far as possible is now necessary given that the warnings
provided by atmospheric phenomena or closely connected to them are now evidence of an
ongoing process, which will strike again and abruptly.
11
Chapter 1
A global perspective on Drought
1.1 Definition of Drought
Drought is an event of a prolonged shortage of water supply or deficiency of precipitation
over an extended period, both of an atmospheric type and therefore implies a series of
rainfall below the seasonal average or of a water type, with surface or groundwater that
undergoes the effects of evaporation and drying up. Generally, a drought lasts for months
or a few years, but it particularly affects the summer period with the possibility of causing
a serious impact on the ecosystem and agriculture of areas of the world in which the
phenomenon takes place with an evident extreme impact, not only from a natural point of
view but also from an economic one.
2
In tropical regions, the summer seasons, which are
usually the driest ones compared to continental climates, increase the possibility that
different types of fires may develop due to heat waves, extremely correlated to the
phenomenon of drought, which can significantly worsen accelerating the evaporation of
water from the soil.
3
Drought is a phenomenon affecting developing countries globally but
is also concentrated and developing year after year in temperate zones.
4
This means that
the phenomenon of drought is an event that is increasingly going to undermine the
climate stability balances of areas of the globe, previously not particularly affected by this
type of event. In general, drought is still a feature that often occurs in different areas of the
world, however, despite this, these regular droughts have become increasingly irregular in
areas of the planet where they did not occur before. The unpredictability of drought itself
is therefore due precisely to climate change, which is manifesting itself in new areas and
2
Wikipedia, Drought, (2022), https://it.wikipedia.org/wiki/Drought, [Last Accessed 13/10/2022].
3
Ibidem.
4
D.A. Wilhite, (2000), Drought as a natural hazard: concepts and definitions, a Global Assessment, Volume I,
Routledge, London (UK), pp. 3-18.
12
regions with often intense, destructive, and extreme atmospheric phenomena of
different types.
The various hydrogeological, hydrographic, and meteorological studies show that there is
an annual increase in drought phenomena and that the events have already begun to change
starting about 1900, to continue in the last decade systematically and more consistently,
showing a precise frequency.
5
Droughts and water shortages can be categorized into mainly
three groups of effects: environmental, economic, and social drought.
6
The environmental
drought in question in this thesis is the type of drought that affects more and more generally
temperate areas, increasing the presence of dry soil and fires with consequent loss of
biodiversity.
7
Consequently, there is also an economic loss following the event and therefore
we can speak of economic drought: the decrease in agricultural, forestry, game and fishing
production generates an increase in food production costs and also the supply of these
resources becomes increasingly difficult, including that, obviously even before food, water,
in short supply for the energy and civil sector, creates critical situations for the population
who is no longer able to be self-sufficient.
The social and health costs are therefore closely related to the negative effects not only on
the surrounding environment but also on the health of the people who are directly exposed
to the phenomenon, generating collective water stress caused by failed crops together with
the high food costs that lead to the occurrence of mass migrations and serious humanitarian
crises that are difficult to deal with.
8
From a human point of view, drought is not only a
phenomenon that can be defined as physical, but it is also an event that marks the breaking
of the balance between the natural availability of water and the consumption caused by
5
European Environmental Agency, (2016), Europe's environment: Second assessment, www.eea.europa.eu,
[Last Accessed 13/10/2022].
6
D. Chan, Q. Wu, (2015), Significant anthropogenic-induced changes of climate classes since 1950, Nature Scientific
Report, Article Number 13487, pp.1-8.
7
ISPRA, (2019), Rapporto sulla siccità, www.isprambiente.gov.it, [Last Accessed 13/10/2022].
8
D. Proietto, (2005), Carestia e siccità in Etiopia, www.politicadomani.it, Politica Domani [Last Accessed
13/10/2022].
Accessed 14/10/2022].
13
human activities.
9
This disruption of the natural balance can cause considerable damage
both to the ecosystem, which faces a serious loss from a natural point of view, and to the
agricultural activities of the areas concerned.
1.1.1 Drought as an increasing phenomenon
Although droughts usually last many years, they can, however, be particularly intense even
in shorter periods such as the case of 2022, particularly difficult in Europe and in various
other areas of the planet due to extreme and somehow unexpected lack of precipitation.
Since drought is a devastating phenomenon in environmental and economic terms, in many
regions of the Earth it is important to use some strategies which, if adopted, include the
right measures to counter it in advance. In terms of records, the world’s longest-lasting
drought in recorded history occurred in Chile’s Atacama Desert and lasted for 400 years.
10
Throughout history, humans have always sought the causes of droughts trying to remedy
them. Drought is a natural threat in the last years have been affected by human activity
which, by altering the water cycles through CO2 emissions for decades, is giving way to so-
called climate change.
11
However, drought is still the subject of numerous criticisms and
scepticism today, as according to some scientists, the phenomenon is and remains cyclical,
unrelated to any artificial activity.
12
Whether or not be a consequence of climate change, the
physical causes of drought are to be found in atmospheric precipitation; these do not
depend only on the presence of water vapour in the atmosphere but also on the
simultaneous ascent of the air masses inside it: if one of these two phenomena is attenuated
9
Ibidem.
10
T. Spano, (2022), È il posto più secco del mondo, non piove da 500 anni, www.ecocultura.it, [Last Accessed
14/10/2022].
11
H. Pörtner, D. C. Roberts, (2022), Report Climate Change 2022: Impacts, Adaptation and Vulnerability Working
Group II Contribution to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change, Chapter 3,
p. 458.
12
E. Ragusa, (2022), Cambiamenti climatici: un crescente scetticismo, www.attivitasolare.com, Attività Solare, [Last
14
it can generate a particular situation of drought. In addition, some factors may influence
such as a prevalence of high pressure which brings dry air masses instead of humid ones;
the oceanic thermal cycles for which there are still numerous studies to be done, as they
have not been fully understood in their complexity. Finally, deforestation reduces soil
moisture and the ability to retain liquids, thus fueling global warming
13
Deforestation is
strongly associated with global warming and hurts crops
14
, especially in developing
countries, where the phenomenon has significant consequences such as the death of
livestock and a reduction in the extension of cultivated fields due to the consequent increase
in desertification.
The population is no longer able to live in an environment that is hostile to human life since
the phenomenon can also create, at least in some cases, sandstorms given that already desert
regions are affected by erosion. The social tensions that result from drought can
subsequently also lead to situations of conflict and wars, generating mass immigration
which is only one of the possible effects. Indeed, conflict-related drought also depends on
several crucial elements such as the vulnerability of the area affected. Where there is a type
of subsistence agriculture it will is very probable that the population arises due to drought
due to a lack of food resources, but the consequences also strongly depend on the social and
political conditions of the country itself.
15
To deal with these problems, generally, in
industrialized countries, some techniques are used to counteract the lack of water
resources, such as desalinating seawater for agricultural or domestic uses. In addition,
constant monitoring of rainfall levels with crop rotation can help minimize erosion and
subsequent crop loss.
16
In conclusion, an efficient and organized collection and purification
13
Climate Action, (2021), Consequences of climate change, climate.ec.europa.EU, [Last Accessed 14/10/2022].
14
Ivi, p.12.
15
Ibidem.
16
The Economist Namibia, (2020), The effects of rainfall distribution and intensity on agricultural production,
https://economist.com.na/57635/columns/the-effects-of-rainfall-distribution-and-intensity- on-crop-
production/, [Last Accessed 14/10/2022].
[Last Accessed 14/10/2022].
15
of rainwater, and the construction of dams, aqueducts and canals can guarantee water
supply in dry areas, despite the absence of water in certain seasons which can lead to water
use restrictionssuch as those applied in Italy in the summer of 2022
17
including a limitation on
the irrigation of lawns, gardens, car washing and the use of swimming pools. These
restrictions can certainly help save water so that we can face the summer season, usually the
most affected, without having to resort to further particular solutions, as the restrictions
themselves certainly generate a water reserve that can cope with the existing crisis but
unfortunately, only for a limited time and as a palliative solutions
18
Extreme weather events
repeated over time still pose a major challenge for agriculture and the sector itself. The
convergence of remote sensing using satellites and supervised learning can generate solutions
for problems arising from drought-related climate change: through a series of available data
and outputs, this function can be used to predict new phenomena. Since, as seen from the
indices, the phenomena are not parametric anyway, it is not possible to extract large
quantities from satellite data to capture the real relationships between climate variables
present on the earthtoday but is it possible to prevent or hypothesize the event to protect the
crops and to develop weather forecasting models. The agricultural index reflects on the water
conditionsof the soil that influence the crops, monitoring events in terms of time to react in
advance and investing resources in the best viable way to deal with them if they occur. In
such a way that these approaches, however, can go to integrate satellite data. Climate change
is modifying rainfall patterns and increasing their severity. The drought of summer 2022 has
reduced crop yields by 40% and 50% in some countries in both northern and central
Europe.
19
Drought is by far the costliest natural disaster on the earth and can have far-
17
F. Cupellaro, (2022), Siccità, la battaglia dell'acqua: Regioni e Comuni chiudono i rubinetti,
https://www.repubblica.it/green-and
blue/2022/06/23/news/siccita_le_regioni_e_i_comuni_chiudono_i_rubinetti, The Republic, [Last Accessed
14/10/2022].
18
Ibidem.
19
Sky TG 24, (2022), Siccità in Europa, 47% del territorio a rischio secondo uno studio dell'Unione Europea, tg24.sky.it,
16
reaching impacts. Notwithstanding the most important analysis of the phenomenon entered
into force in 1947, there is no evidence that tolerance to water stress has improved in recent
years, indeed, the perception is negative
20
. Therefore, drought forecasts are important to
determine when to take emergency actions to prevent them to mitigate the risks and the
impact itself. The practice of in-depth forecasting remains challenging and is however
subject to great uncertainty as in part it is due to the instability of the hydrogeological cycle
itself.
21
Over the years, it has demonstrated an oscillating behaviour made up of sudden
changes that appear in the hydroclimate register as unexpected. One of the priorities of
climate science is the development of reliable data sets for understanding climate processes
on a global scale. Most of the efforts have recently been devoted to developing a global
gridded dataset with various climate variables, including temperature, precipitation, and
pressures across different areas of the globe.
22
Despite the usefulness of these data, there is
a need to adjust baseline climate parameters and this summary information on wet and
drought conditions. These are the primary data points valued by environmental,
hydrological, and global change researchers and are crucial for determining possible
variable effects regarding the drought. The best approach is developed through the
measurement of relative humidity in different areas of the world and of dryness to calculate
the highest drought indexes given by the combination of these two factors.
1.1.2 Forecast droughts through indexes
The most important indexes are the Palmer drought severity index (PDSI)
23
which is one of
20
G. Ondrasek, L. Ornella, G. Kruseman and J. Crossa, (2019), Drought Detection and Solutions, Satellite Data
and Supervised Learning to Prevent Impact of Drought on Crop Production: Meteorological Drought, London (UK),
Chapter 1, p. 1, [Last Accessed 14/10/2022].
21
Ibidem.
22
Integrated National Drought Information System, (2022), www.drought.gov, [Last Accessed 14/10/2022].
23
NCAR, (2023), Climate Data Guide, https://climatedataguide.ucar.edu/climate-data/palmer-drought-
severity-index-psi, [Last Accessed 14/10/2022].
17
the most used to verify the water and climate balance and considers the anomalies in rainfall
and the phenomenon of evapotranspiration, the soil water retention capacity.
24
The index
has reported extreme humidity and drought cases over the years, at frequencies never seen
before and in rare conditions. The time scale used does not allow us to distinguish the three
diverse types of droughts (economic, social, and environmental), since drought is
considered a multi-scalar phenomenon, an event that can occur simultaneously on several
time scales. For example, a critical short dry spell may also occur within a less intense long
dry spell. Both drought and aridity indicate an imbalance in water availability, while
drought is a real danger to human survival in areas prone to it. In addition, aridity is a
constant climatic feature in which the potential for evapotranspiration can be assessed as a
means of understanding resilience in a warming climate. Another index used and
recognized internationally is the standardized precipitation evapotranspiration index
(SPEI)
25
based on the rainfall present in each season.
seasons indices together are used to understand the results that emerge from the different
experiences of drought and the various trends of storm phenomena in different parts of the
globe with climates from humid, semi-arid and sub-humid zones. The conclusion of the
detailed analysis from the year 1936
26
, provided by the Journal of Hydrometeorology shows
that the indices have had different and generally decreasing trends. The SPEI was not
largely comparable to the PDSI in that both indices considered water inputs by precipitation
and water outputs by evapotranspiration today, however, comparing the SPEI and PDSI
datasets globally demonstrates that they both have a rigid time scale, and this means that
the correlation exists even at the level of certified data: when a drought condition is recorded
24
A. K. Mishra, V. P. Singh, (2010), Prevision of Drought, Texas (USA), Chapter 2, p. 157–175, Journal of
Hydrology, [Last Accessed 14/10/2022].
25
NCAR, (2023), Climate Data Guide, https://climatedataguide.ucar.edu/climate-data/standardized-
precipitation-evapotranspiration-index-spei, [Last Accessed 14/10/2022].
26
S.M. Vincente Serrano, (2010), Drought Global Index Database, Volume 11, p. 1035, American Meteorological
Society, Journal of Hydrometeorology, [Last Accessed 14/10/2022].
18
with the SPEI on a particular time scale,
27
it is possible with certainty to scientifically
demonstrate and establish that the drought is caused by a cumulative deficit of rainfall
and/or excessive evapotranspiration (compared to average conditions) and therefore it is
possible to predict the next level of drought on a reliable time scale for 12-18 months;
exceeding this period the index it would prove to be inaccurate as it is imposed only for
intermediate periods, not too short or too long.
28
Although severe droughts have always
occurred in some areas and have been very intense in the summer periods, it has also been
possible to demonstrate that the drought conditions began to be particularly severe on a
global scale around the 1940s
29
, while on longer time scales these episodes were not
recognized due to the intrinsic limitation of the indicators, thus deducing from that year in
particular, a correlation with human activities that were increasing massive
industrialization In summary, these examples show that existing drought datasets based on
these two indices are too strict to identify droughts of different time scales in the short and
long term, but the relative conditions of dryness and wetness can still be measured in the
medium term, finding the correlations to the phenomena, and introducing actions to
prevent them and therefore not just limiting themselves to predicting them. In short, due to
the great complexity of the effects of drought, the Journal of Meteorological Hydrogeology
30
deals with identifying different sectors and natural systems that include a rigorous
probabilistic nature. The index provides objective information on drought climatic
conditions, as it is not influenced by external variables, but is based only on concrete climatic
data. In any case, there would be other factors to consider such as the activity of the
27
McKee, T.B. Doesken, NJ. Kleist, (1993), The relationship of drought frequency and duration to time scales, Paper
Presented at 8th Conference on Applied Climatology, American Meteorological Society, Anaheim, California
(USA), pp. 17-22.
28
B. Fernandez, A. Vergara, (1998), Risk of the scarcity of monthly precipitation and stream flows in semiarid regions.
Hydrology Science Journal, 43 (5), 759–773, [Last Accessed 14/10/2022].
29
Ibidem.
30
Ibidem.
19
vegetation in the steppe areas, in the arid cereal-growing areas of the semi-arid regions as
happens in the Iberian Peninsula, for example on short time scales of 3-6 months
31
capable
of influencing the drought phenomenon, while forests responded more to longer timescales
but were unable to survive and cope with it in the short term if as intense as summer 2022.
In Conclusion, droughts have occurred very frequently in different parts of the world and
the impacts have aggravated the hydrogeological situation in all countries the water
demand has grown exponentially but due to climate change, it is no longer possible to
meet it with the consequence that in the temperate zones studies are focusing a great deal
of attention and applying a different variety of concepts to rough modelling, ranging from
simplistic to extremely complex approaches based on a multitude of data, remembering
that meteorology is not an exact science, as modelling approaches have both advantages
and limitations.
The various papers published in the authoritative 'Journal of Hydrology dealt with the
integration of several drought concepts into previous data from 2010
32
, in which recent
updates on probability-based models and analysing the space-time of global climate
models, increasingly focusing on probable drought scenarios to build a reliable system on
terrestrial data. For efficient modelling and planning, it was found that large-scale climate
indices in the temperate areas of the world appear to be promising for forecasting even long-
term droughts, as the original indices with the studies seen above were only able to define
predictable phenomena in the medium and short term. There have therefore been
significant improvements at a scientific level in recent decades, and the use of hybrid
models, which have now become crucial to the work in this regard, have seemed the best,
as they include a vast amount of data that is often difficult to analyse but can give hopeful
results on the applications of these models to drought, trying to identify a certain
characterization of drought to understand its real effects, obviously including rainfall as a
fundamental element in defining its severity for risk assessment and the adoption of
31
A. K. Mishra, V. P. Singh, (2011), Drought modelling – A review, Journal of Hydrology, [Last Accessed
14/10/2022].
32
Ibidem.
20
precautionary measures subsequently developed through a flow of useful information for
users. However, climate change does not yet seem to be clearly defined, and even though
the temperate zones of the world have a greater capacity to restore their natural balances
momentarily, developing countries do not seem to be able to cope with the phenomena also
due to the inexorable growth of the population at a global level, which has recently reached
eight billion people and is mainly occurring in these very countries, the direction seems to
be that of being close to environmental collapse if there isn't a sudden change. The
expansion of the agricultural, energy and industrial sectors worldwide also continues to
contribute to climate imbalance and the contamination of vital water resources, which are
becoming increasingly scarce. Therefore, understanding the patterns and the attention paid
by ecologists, hydrologists, and meteorologists to the phenomenon around the world is a
priority for future joint management of resources and planning for their reuse and saving.
In concrete terms, the hydrogeology variables for drought are still rainfall, temperature
flows, evaporation, soil moisture, water in aquifers and their levels. Together with these
variables, a rough index can be established, allowing the methodology of regression
33
models and historical probability models to be developed, which can become hybrids
34
if
they are cross-referenced with additional climate data available to us such as sea
temperature levels, ocean fluctuations, wind, and atmospheric pressure data. In this way,
the production of data could deliver clues on the initiation and cessation of the phenomenon
by understanding its nature, severity, and likelihood of recurrence. Hybrid models
35
are,
however, useful for extracting drought predictions, as they have greater accuracy.
33
V. Kumar, U. Panu, (1997), Predictive assessment of the severity of agricultural droughts based on agro-climatic
factors, American Journal of Water Resources Association, 33 (6), pp. 1255–1264.
34
T. Kim, J.B. Valdes, (2003), Nonlinear model for drought forecasting based on a conjunction of wavelet transforms
and neural networks, Journal of Hydrology, Eng., ASCE 8 (6), pp. 319–328.
35
Ibidem.
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