scholarly journals From meteorological to hydrological drought using standardised indicators

2015 ◽  
Vol 12 (12) ◽  
pp. 12827-12875 ◽  
Author(s):  
L. J. Barker ◽  
J. Hannaford ◽  
A. Chiverton ◽  
C. Svensson
Keyword(s):  
Time Series ◽  
Hydrological Drought ◽  
Strongly Correlated ◽  
Propagation Characteristics ◽  
The South ◽  
Drought Characteristics ◽  
The North ◽  
The One ◽  
The Uk ◽  
Hydrological Droughts

Abstract. Drought monitoring and early warning (M&EW) systems are a crucial component of drought preparedness. M&EW systems typically make use of drought indicators such as the Standardised Precipitation Index (SPI), but such indicators are not widely used in the UK. More generally, such tools have not been well developed for hydrological (i.e. streamflow) drought. To fill these research gaps, this paper characterises meteorological and hydrological droughts, and the propagation from one to the other using the SPI and the related Standardised Streamflow Index (SSI), with the objective of improving understanding of the drought hazard in the UK. SPI and SSI time series were calculated for 121 near-natural catchments in the UK for accumulation periods of 1–24 months. From these time series, drought events were identified and for each event, the duration and severity was calculated. The relationship between meteorological and hydrological drought was examined by cross-correlating the one month SSI with various SPI accumulation periods. Finally, the influence of climate and catchment properties on the drought characteristics and propagation were investigated. Results showed that at short accumulation periods meteorological drought characteristics showed little spatial variability, whilst hydrological drought characteristics showed fewer but longer and more severe droughts in the south and east than in the north and west of the UK. Propagation characteristics showed a similar spatial pattern with catchments underlain by productive aquifers, mostly in the south and east, having longer SPI accumulation periods strongly correlated with the one-month SSI. For catchments in the north and west of the UK, which typically have little catchment storage, standard-period annual average rainfall was strongly correlated to drought and propagation characteristics. However, in the south and east, catchment properties describing storage, such as base flow index, percentage of highly productive fractured rock and typical soil wetness, were more influential on drought characteristics. This knowledge forms a basis for more informed application of standardised indicators in the UK in future, which could aid in the development of improved M&EW systems. Given the paucity of studies applying standardised indicators to hydrological droughts, and the diversity of catchment types encompassed here, the findings could prove valuable for enhancing the hydrological aspects of M&EW systems elsewhere in the world.

scholarly journals From meteorological to hydrological drought using standardised indicators

2016 ◽  
Vol 20 (6) ◽  
pp. 2483-2505 ◽  
Author(s):  
Lucy J. Barker ◽  
Jamie Hannaford ◽  
Andrew Chiverton ◽  
Cecilia Svensson
Keyword(s):  
Time Series ◽  
Hydrological Drought ◽  
Annual Rainfall ◽  
Strongly Correlated ◽  
Propagation Characteristics ◽  
The South ◽  
Drought Characteristics ◽  
The North ◽  
The Uk ◽  
Hydrological Droughts

Abstract. Drought monitoring and early warning (M & EW) systems are a crucial component of drought preparedness. M & EW systems typically make use of drought indicators such as the Standardised Precipitation Index (SPI), but such indicators are not widely used in the UK. More generally, such tools have not been well developed for hydrological (i.e. streamflow) drought. To fill these research gaps, this paper characterises meteorological and hydrological droughts, and the propagation from one to the other, using the SPI and the related Standardised Streamflow Index (SSI), with the objective of improving understanding of the drought hazard in the UK. SPI and SSI time series were calculated for 121 near-natural catchments in the UK for accumulation periods of 1–24 months. From these time series, drought events were identified and for each event, the duration and severity were calculated. The relationship between meteorological and hydrological drought was examined by cross-correlating the 1-month SSI with various SPI accumulation periods. Finally, the influence of climate and catchment properties on the hydrological drought characteristics and propagation was investigated. Results showed that at short accumulation periods meteorological drought characteristics showed little spatial variability, whilst hydrological drought characteristics showed fewer but longer and more severe droughts in the south and east than in the north and west of the UK. Propagation characteristics showed a similar spatial pattern with catchments underlain by productive aquifers, mostly in the south and east, having longer SPI accumulation periods strongly correlated with the 1-month SSI. For catchments in the north and west of the UK, which typically have little catchment storage, standard-period average annual rainfall was strongly correlated with hydrological drought and propagation characteristics. However, in the south and east, catchment properties describing storage (such as base flow index, the percentage of highly productive fractured rock and typical soil wetness) were more influential on hydrological drought characteristics. This knowledge forms a basis for more informed application of standardised indicators in the UK in the future, which could aid in the development of improved M & EW systems. Given the lack of studies applying standardised indicators to hydrological droughts, and the diversity of catchment types encompassed here, the findings could prove valuable for enhancing the hydrological aspects of drought M & EW systems in both the UK and elsewhere.

The Villa Item and a Bride's Ordeal

1929 ◽  
Vol 19 (1) ◽  
pp. 67-87 ◽  
Author(s):  
Jocelyn Toynbee
Keyword(s):  
The South ◽  
Important Paper ◽  
The North ◽  
Dwelling House ◽  
South Wall ◽  
The Subject ◽  
The One ◽  
The Individual ◽  
North Wall ◽  
The Right

The paintings in the triclinium of the Villa Item, a dwelling-house excavated in 1909 outside the Porta Ercolanese at Pompeii, have not only often been published and discussed by foreign scholars, but they have also formed the subject of an important paper in this Journal. The artistic qualities of the paintings have been ably set forth: it has been established beyond all doubt that the subject they depict is some form of Dionysiac initiation: and, of the detailed interpretations of the first seven of the individual scenes, those originally put forward by de Petra and accepted, modified or developed by Mrs. Tillyard appear, so far as they go, to be unquestionably on the right lines. A fresh study of the Villa Item frescoes would seem, however, to be justified by the fact that the majority of previous writers have confined their attention almost entirely to the first seven scenes—the three to the east of the entrance on the north wall (fig. 3), the three on the east wall and the one to the east of the window on the south wall, to which the last figure on the east wall, the winged figure with the whip, undoubtedly belongs.

scholarly journals Reflections on a field across time and space: the emergent medical and health humanities in South Africa

2018 ◽  
Vol 44 (4) ◽  
pp. 263-269 ◽  
Author(s):  
Victoria Jane Hume ◽  
Megan Wainwright
Keyword(s):  
South Africa ◽  
South African ◽  
Cross Cultural ◽  
The South ◽  
Health Humanities ◽  
Cultural Experience ◽  
The North ◽  
Qualitative Evidence ◽  
The Uk ◽  
Personal Reflections

In this paper, we draw on our own cross-cultural experience of engaging with different incarnations of the medical and health humanities (MHH) in the UK and South Africa to reflect on what is distinct and the same about MHH in these locations. MHH spaces, whether departments, programmes or networks, have espoused a common critique of biomedical dualism and reductionism, a celebration of qualitative evidence and the value of visual and performative arts for their research, therapeutic and transformative social potential. However, there have also been differences, and importantly a different ‘identity’ among some leading South African scholars and practitioners, who have felt that if MHH were to speak from the South as opposed to the North, they would say something quite different. We seek to contextualise our personal reflections on the development of the field in South Africa over recent years within wider debates about MHH in the context of South African academia and practice, drawing in part on interviews conducted by one of the authors with South African researchers and practitioners and our own reflections as ‘Northerners’ in the ‘South’.

Numerical Analysis of Ebb Water Split Ratio of the South and North Branch in the Changjiang Estuary

2013 ◽  
Vol 807-809 ◽  
pp. 1624-1627
Author(s):  
Ji Zhong Yang ◽  
Jie Gu ◽  
Dan Qing Ma ◽  
Xiao Li Wang ◽  
Tian Hu ◽  
...  
Keyword(s):  
Spring Tide ◽  
Changjiang Estuary ◽  
The South ◽  
The Changjiang Estuary ◽  
Hydrodynamic Analysis ◽  
The North ◽  
Split Ratio ◽  
Calculation Results ◽  
Set Up ◽  
The One

The change of water split ratio has important impacts on the fluvial process, saltwater intrusion and navigation in estuary area. A 2D hydrodynamics numerical model of the Changjiang Estuary was set up using Delft3D-FLOW. The calculation results are consistent well with the real measured data, which indicates that the model can be used in hydrodynamic analysis. Simulation results show that the ebb water split ratio of the North Branch in the flood season is larger than that in the dry season, while the situation of the South Branch is opposite. Under the condition of different tidal types, the ebb water split ratio for the North Branch is maximum during the spring tide, and minimum during the neap tide, while the one during the middle tide takes the second place.

Cold Induced Abnormal Catches of Sole

1998 ◽  
Vol 78 (1) ◽  
pp. 345-347 ◽  
Author(s):  
J.W. Horwood ◽  
R.S. Millner
Keyword(s):  
North Sea ◽  
Cold Water ◽  
The South ◽  
Total Allowable Catch ◽  
The North ◽  
Solea Solea ◽  
The North Sea ◽  
The Uk ◽  
The Eu ◽  
Made In

Large catches of sole (Solea solea) were made in early 1996 from the south-western North Sea. Sole suffer physiological damage in waters below 3–4 C. In February 1996 cold water of 3–4 C unusually extended from the Continental coast onto the Dogger Bank. It is likely that the increased catches were due to the consequential distribution and behaviour of the sole, making them more susceptible to capture.Exceptionally large catches of mature sole (Solea solea (L.)) were made in February 1996 by Lowestoft fishermen from the south-western North Sea. Surprisingly this was not welcome. The UK allocation of the North Sea sole is -4 % of the EU Total Allowable Catch (TAC), and fishermen are restricted nationally, and by the fishing companies, to a tightly managed ration. The Lowestoft Journal (8 March 1996) reported the suspension of a local fishing skipper for not throwing back 5000 kg of sole caught in the Silver Pits. We will show that the abnormal catches were due to exceptionally cold waters.Sole in the North Sea are at the northern extremity of their range, with sole seldom living in waters below 5°C (Horwood, 1993). In fact, North Sea sole were successfully introduced into Lake Quarun, Egypt, where they lived in temperatures in excess of 30°C (El-Zarka, 1965). Young sole migrate from their shallow inshore nursery grounds, such as the Waddensea, as winter approaches (Creutzberg & Fonds, 1971).

scholarly journals THE SOUTH-EASTERN BORDER REGION OF THE HITTITE STATE

2016 ◽  
pp. 19-30
Author(s):  
ROBERT GHAZARYAN
Keyword(s):  
Border Region ◽  
The Other ◽  
The South ◽  
The North ◽  
Other Hand ◽  
Euphrates Valley ◽  
Important Position ◽  
The One ◽  
The Right ◽  
Armenian Highland

Tegarama was one of the eastern lands of the Hittite Kingdom. In the geographic sense it is part of the Armenian Highland that is why its history is of special interest to us. Taking into account the fact that the Armenian people had considerable ethnic ties with the Upper Euphrates region, specialists have traditionally tended to identify “Home of Torgom” in the Trans Euphrates region together with the city Tegarama (Assyrian Til-Garimmu) mentioned from the 2nd millennium BC. “Home of Torgom” literally repeats Bet-Togarma mentioned in the Bible. The study of the history of the country of Tegarama is also important because in Armenian historiography, starting from Movses Khorenatsi, Armenian ancestor Hayk is called “Son of Torgom”, and the Armenian people - “People of Torgom”. Most of the researchers located Tegarama in the place of the present settlement Gyurun. By comparing the “Cappadocian”, Hittite and Assyrian sources, Tegarama can be located in the Upper Euphrates valley, on the right bank of the river, to the north of Kargamis, to the west of Isuwa, to the south of Upper Land and to the east of Kanes. The territory of Tegarama was not far from Nesa - one of the initial centers of the Hittites; and it was also one of the initial places of inhabitance of the Hittites. Tegarama also occupied a strategically important position. On the one hand it bordered on the country of Mitanni, on the other hand - on Isuwa. Thus, the country of Tegarama occupied a significant geographic position: on the one hand roads led from here to other western districts of the Armenian Highland, to Tsopk, and on the other hand - to Northern Syria and Northern Mesopotamia. It was also one of the spiritual centers of Hatti.

scholarly journals On the spatial segregation of helicity by inertial waves in dynamo simulations and planetary cores

2018 ◽  
Vol 851 ◽  
pp. 268-287 ◽  
Author(s):  
P. A. Davidson ◽  
A. Ranjan
Keyword(s):  
Numerical Simulations ◽  
Strongly Correlated ◽  
Inertial Waves ◽  
The South ◽  
The North ◽  
Planetary Cores ◽  
Local Wave ◽  
Wave Flux ◽  
The Relationship

The distribution of kinetic helicity in a dipolar planetary dynamo is central to the success of that dynamo. Motivated by the helicity distributions observed in numerical simulations of the Earth’s dynamo, we consider the relationship between the kinetic helicity, $h=\boldsymbol{u}\boldsymbol{\cdot }\unicode[STIX]{x1D735}\times \boldsymbol{u}$, and the buoyancy field that acts as a source of helicity, where $\boldsymbol{u}$ is velocity. We show that, in the absence of a magnetic field, helicity evolves in accordance with the equation $\unicode[STIX]{x2202}h/\unicode[STIX]{x2202}t=-\unicode[STIX]{x1D735}\boldsymbol{\cdot }\boldsymbol{F}+S_{h}$, where the flux, $\boldsymbol{F}$, represents the transport of helicity by inertial waves, and the helicity source, $S_{h}$, involves the product of the buoyancy and the velocity fields. In the numerical simulations it is observed that the helicity outside the tangent cylinder is predominantly negative in the north and positive in the south, a feature which the authors had previously attributed to the transport of helicity by waves (Davidson & Ranjan, Geophys. J. Intl, vol. 202, 2015, pp. 1646–1662). It is also observed that there is a strong spatial correlation between the distribution of $h$ and of $S_{h}$, with $S_{h}$ also predominantly negative in the north and positive in the south. This correlation tentatively suggests that it is the in situ generation of helicity by buoyancy that establishes the distribution of $h$ outside the tangent cylinder, rather than the dispersal of helicity by waves, as had been previously argued by the authors. However, although $h$ and $S_{h}$ are strongly correlated, there is no such correlation between $\unicode[STIX]{x2202}h/\unicode[STIX]{x2202}t$ and $S_{h}$, as might be expected if the distribution of $h$ were established by an in situ generation mechanism. We explain these various observations by showing that inertial waves interact with the buoyancy field in such a way as to induce a source $S_{h}$ which has the same sign as the helicity in the local wave flux, and that the sign of $h$ is simply determined by the direction of that flux. We conclude that the observed distributions of $h$ and $S_{h}$ outside the tangent cylinder are consistent with the transport of helicity by waves.

scholarly journals Less Frequent but More Severe Hydrological Drought Events Emerge at 1.5 and 2 °C Warming Levels over the Wudinghe Watershed in northern China

2018 ◽  
Author(s):  
Yang Jiao ◽  
Xing Yuan
Keyword(s):  
Land Surface ◽  
Climate Models ◽  
Coupled Model ◽  
Northern China ◽  
Hydrological Drought ◽  
Drought Severity ◽  
Drought Frequency ◽  
Drought Characteristics ◽  
The Impact ◽  
Hydrological Droughts

Abstract. Assessment of changes in hydrological droughts at specific warming levels (e.g., 1.5 or 2 °C) is important for an adaptive water resources management with consideration of the 2015 Paris Agreement. However, most studies focused on the response of drought frequency to the warming and neglected other drought characteristics including severity. By using a semiarid watershed in northern China (i.e., Wudinghe) as an example, here we show less frequent but more severe hydrological drought events emerge at both 1.5 and 2 °C warming levels. We used meteorological forcings from eight Coupled Model Intercomparison Project Phase 5 climate models with four representative concentration pathways, to drive a newly developed land surface hydrological model to simulate streamflow, and analyzed historical and future hydrological drought characteristics based on the Standardized Streamflow Index. The Wudinghe watershed will reach the 1.5 °C (2 °C) warming level around 2006–2025 (2019–2038), with an increase of precipitation by 6 % (9 %) and runoff by 17 % (27 %) as compared to the baseline period (1986–2005). This results in a drop of drought frequency by 26 % (27 %). However, the drought severity will rise dramatically by 63 % (30 %), which is mainly caused by the increased variability of precipitation and evapotranspiration. The climate models contribute to more than 82 % of total uncertainties in the future projection of hydrological droughts. This study suggests that different aspects of hydrological droughts should be carefully investigated when assessing the impact of 1.5 and 2 °C warming.

Rebel Retirement in the North through Discordant Exit Networks

2021 ◽  
pp. 118-143
Author(s):  
Rumela Sen
Keyword(s):  
The Other ◽  
Grassroots Organizations ◽  
Gray Zone ◽  
The South ◽  
The North ◽  
Other Hand ◽  
Land Relations ◽  
State Agents ◽  
The One

This chapter shows how weak grassroots organizations in the gray zone of state-insurgency interface led to scrawny informal exit networks in the North, discouraging rebel retirement and restricting their reintegration. The differences with the South stem from the secret and semi-secret ties that northern rebels build with state agents like police, politicians, and bureaucracy on the one hand and various nonstate agents like mafias and businesses on the other hand. These ties, alongside distinctive caste/class dynamics and land relations in the North, induces dominance of perverse criminality and spews intense militancy in the North, which vitiates the gray zone of state-insurgency interface.

scholarly journals XII. On a tendency observed in Sun-spots to change alternately from the one solar hemisphere to the other

1873 ◽  
Vol 21 (139-147) ◽  
pp. 399-402
Keyword(s):  
The Other ◽  
The South ◽  
The North ◽  
Other Hand ◽  
Spot Activity ◽  
Sun Spots ◽  
The One

1. Hitherto in our reductions we have summed up the spotted areas of the various groups occurring on the sun’s surface on any day, and have regarded their sum as a representation of the spot-activity for that day. It has occurred to us to see what result we should obtain by taking instead for each day the excess of the spotted area in the one solar hemisphere above that in the other. 2. On adopting this method, it soon became evident that during periods of great disturbance there is a tendency in spots to change alternately from the north or positive to the south or negative hemisphere, and vice versâ , the period of such change being about 25 days. When, on the other hand, the solar disturbance is inconsiderable, the spots do not present any such systematic oscillation.

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