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Assessing long term flash flooding frequency using historical information

David R. Archer, Geoff Parkin, Hayley J. Fowler
2016 Hydrology Research  
Flash floods are distinguished from "normal flooding" by an abrupt onset arising from intense short period rainfall. Historical information based on pre-gauged descriptive information is used to prepare time series of flash floods for Northeast England and Southwest England as decadal numbers of events from 1800. The time series show a minimum in the late twentieth century for both locations. Flash flood frequency is then assessed for three locations in Northeast England by comparing recent
more » ... eme floods with historical accounts: 1) an urban pluvial flood in Newcastle in June 2012, 2) a severe flood in September 1968 on the Cotting Burn, a small ungauged tributary of the River Wansbeck, and 3) an extreme rate of rise in river level on the River Wansbeck in August 1994. Although there have been no comparable recent occurrences, several flash floods of equal or greater magnitude at the same locations were identified from historical accounts. Using the longer historical record in conjunction with limited recent observations has advantages when assessing the frequency of occurrence of rare events. However, these advantages are tempered by the possibility of non-stationarity in the historical series owing to catchment changes, from natural climatic variability and from potential anthropogenic climate change.
doi:10.2166/nh.2016.031 fatcat:jndr7cx2brhlneyxcgt6mujizi

Parsimonious numerical modelling of deep geothermal reservoirs

Tim H. Fairs, Paul L. Younger, Geoff Parkin
2015 Proceedings of the ICE - Energy  
The approach used and results presented in this study are 1 Energy Parsimonious numerical modelling of deep geothermal reservoirs Fairs, Younger and Parkin Proceedings of the Institution of Civil Engineers  ...  Units are as in Table 2 Energy Parsimonious numerical modelling of deep geothermal reservoirs Fairs, Younger and Parkin Figure 1 . 1 Geological map of the North Pennines of England (simplified after  ...  Energy Parsimonious numerical modelling of deep geothermal reservoirs Fairs, Younger and Parkin heat transport model is most sensitive to parameters related to convective heat transport and this supports  ... 
doi:10.1680/ener.14.00026 fatcat:4tvtqblewfhapjq6b2cn24bef4

SHETRAN: Distributed River Basin Flow and Transport Modeling System

John Ewen, Geoff Parkin, Patrick Enda O'Connell
2000 Journal of hydrologic engineering  
This criticism has been addressed in Ewen and Parkin (1996) and Parkin et al. (1996) .  ...  To create SHETRAN Version 4, the subject of this paper, the column approach was extended to subsurface flow (Parkin 1996) .  ... 
doi:10.1061/(asce)1084-0699(2000)5:3(250) fatcat:44u53vpfkrfitc24nxxmboau5i

Parsimonious numerical modelling of deep geothermal reservoirs

Tim H. Fairs, Paul L. Younger, Geoff Parkin
2015 Proceedings of the ICE - Energy  
The approach used and results presented in this study are 1 Energy Parsimonious numerical modelling of deep geothermal reservoirs Fairs, Younger and Parkin Proceedings of the Institution of Civil Engineers  ...  Units are as in Table 2 Energy Parsimonious numerical modelling of deep geothermal reservoirs Fairs, Younger and Parkin Figure 1 . 1 Geological map of the North Pennines of England (simplified after  ...  Energy Parsimonious numerical modelling of deep geothermal reservoirs Fairs, Younger and Parkin heat transport model is most sensitive to parameters related to convective heat transport and this supports  ... 
doi:10.1680/jener.14.00026 fatcat:t6atov3te5cmnou5m5bv25rgua

Slow Living, by Wendy Parkins and Geoff Craig

Julia Hobson Haggerty
Parkins and Craig depict a vital force emerging in food, farm and urban design politics.  ...  As with most rich scholarship, Slow Living raises many important questions that fall outside the scope of Parkins and Craig's original project.  ... 
doi:10.48416/ijsaf.v14i.305 fatcat:4wn3d2oeqrf5fijmzhgjtyxgai

Insights From a Multi-Method Recharge Estimation Comparison Study

David Walker, Geoff Parkin, Petra Schmitter, John Gowing, Seifu A. Tilahun, Alemseged T. Haile, Abdu Y. Yimam
2018 Ground Water  
Although most recharge estimation studies apply multiple methods to identify the possible range in recharge values, many do not distinguish clearly enough between inherent uncertainty of the methods and other factors affecting the results. We investigated the additional value that can be gained from multi-method recharge studies through insights into hydrogeological understanding, in addition to characterizing uncertainty. Nine separate groundwater recharge estimation methods, with a total of
more » ... variations, were applied at a shallow aquifer in northwest Ethiopia in the context of the potential for shallow groundwater resource development. These gave a wide range of recharge values from 45 to 814 mm/a. Critical assessment indicated that the results depended on what the recharge represents (actual, potential, minimum recharge or change in aquifer storage), and spatial and temporal scales, as well as uncertainties from application of each method. Important insights into the hydrogeological system were gained from this detailed analysis, which also confirmed that the range of values for actual recharge was reduced to around 280-430 mm/a. This study demonstrates that even when assumptions behind methods are violated, as they often are to some degree especially when data are limited, valuable insights into the hydrogeological system can be gained from application of multiple methods. Article impact statement: Analysis of common recharge methods shows the value of extracting additional information to improve hydrogeological understanding.
doi:10.1111/gwat.12801 pmid:29896911 fatcat:5w53sau3yba4fpzkr54v4bamhe

The Guiana Shield rainforests—overlooked guardians of South American climate

C Isabella Bovolo, Thomas Wagner, Geoff Parkin, David Hein-Griggs, Ryan Pereira, Richard Jones
2018 Environmental Research Letters  
Tropical forests are global climate regulators through their interaction with hydrological and biogeochemical cycles. Despite extensive research on deforestation in South America and its global impact, the role of the largely intact Guiana Shield forests, north of the Amazon, has not yet been considered as part of this climate system. We use a regional climate model with a realistic deforestation scenario to test the impact of deforestation in the Guiana Shield on climate throughout South
more » ... a. We show that replacing ∼28% of the current Guiana Shield rainforest with savannah leads to multi-scale impacts across South America, through vegetation-land-atmosphere interactions that disrupt the initial phase of two major 'atmospheric rivers': the Caribbean low-level Jet and the South American low-level jet (SALLJ). Our climate simulations suggest that following deforestation, locally, precipitation and runoff would more than double in lowland forests, whilst mean annual temperatures would increase by up to 2.2 • C in savannahs. Regionally, significant wetting is simulated in northern South America (April−September) and the western Amazon (October-March), while temperatures increase up to 2 • C in central and eastern Amazon, causing more dry months in up to 64% of the Amazon basin. Reduction of moisture transfer by the SALLJ of 2.2% of total annual flow causes noticeable and highly diverse spatial changes in simulated monthly rainfall in la plata basin (LPB). These results highlight the potential consequences of land cover change in a sensitive hot-spot with hydro-climatic impacts 1000 km west and 4000 km south. Such multi-scale perturbations can severely impact biodiversity and ecosystem services across South America, including agriculture in LPB. Recognition of the far field effects of localised deforestation in key areas is urgently needed to improve development plans for a sustainable future. Significance statement The Guiana Shield, at the northern boundary of Amazonia, is located at the start of two atmospheric rivers which carry moisture across South America. We show that deforesting less than a third of the Guiana Shield, in areas currently under threat from mining, logging and agricultural activities, could result in significant changes in the water cycle across the continent. This includes large variations in temperature and precipitation affecting areas 4000 km away, impacting ecosystems and economies, with consequences for society. The study demonstrates how land-use change, even if small in spatial scale, but occurring in particularly sensitive hot-spots, can alter the flow of atmospheric rivers, with large consequences. This pan-continental cascade must be considered when designing trans-national management plans for a sustainable future.
doi:10.1088/1748-9326/aacf60 fatcat:fau6marjo5bmbewn72ixevjtjm

Development of a Hydrogeological Conceptual Model for Shallow Aquifers in the Data Scarce Upper Blue Nile Basin

David Walker, Geoff Parkin, John Gowing, Alemseged Tamiru Haile
2019 Hydrology  
Rural communities in sub-Saharan Africa commonly rely on shallow hand-dug wells and springs; consequently, shallow aquifers are an extremely important water source. Increased utilisation of shallow groundwater could help towards achieving multiple sustainable development goals (SDGs) by positively impacting poverty, hunger, and health. However, these shallow aquifers are little studied and poorly understood, partly due to a paucity of existing hydrogeological information in many regions of
more » ... aharan Africa. This study develops a hydrogeological conceptual model for Dangila woreda (district) in Northwest Ethiopia, based on extensive field investigations and implementation of a citizen science programme. Geological and water point surveys revealed a thin (3–18 m) weathered volcanic regolith aquifer overlying very low permeability basalt. Hydrochemistry suggested that deep groundwater within fractured and scoriaceous zones of the basalt is not (or is poorly) connected to shallow groundwater. Isotope analysis and well monitoring indicated shallow groundwater flow paths that are not necessarily coincident with surface water flow paths. Characteristics of the prevalent seasonal floodplains are akin to "dambos" that are well-described in literature for Southern Africa. Pumping tests, recharge assessments, and hydrometeorological analysis indicated the regolith aquifer shows potential for increased utilisation. This research is transferrable to the shallow volcanic regolith aquifers that overlie a substantial proportion of Ethiopia and are prevalent throughout the East African Rift and in several areas elsewhere on the continent.
doi:10.3390/hydrology6020043 fatcat:vhoeakvjnrdtpjmdnzphrpqdr4

Demonstrating the value of community-based ('citizen science') observations for catchment modelling and characterisation

Eleanor Starkey, Geoff Parkin, Stephen Birkinshaw, Andy Large, Paul Quinn, Ceri Gibson
2017 Journal of Hydrology  
Newcastle University ePrints Starkey E, Parkin G, Birkinshaw S, Large A, Quinn P, Gibson C.  ...  ., 2014; Starkey and Parkin, 2015) .  ...  See above-mentioned references for further information.) ing it to obtain discharge information for a variety of applications (Birkinshaw et al., 2011 (Birkinshaw et al., , 2014 Mourato et al., 2015; Parkin  ... 
doi:10.1016/j.jhydrol.2017.03.019 fatcat:sdjb646zlffyhpih3i7zhdxbke

Filling the observational void: Scientific value and quantitative validation of hydrometeorological data from a community-based monitoring programme

David Walker, Nathan Forsythe, Geoff Parkin, John Gowing
2016 Journal of Hydrology  
s u m m a r y This study shows how community-based hydrometeorological monitoring programmes can provide reliable high-quality measurements comparable to formal observations. Time series of daily rainfall, river stage and groundwater levels obtained by a local community in Dangila woreda, northwest Ethiopia, have passed accepted quality control standards and have been statistically validated against formal sources. In a region of low-density and declining formal hydrometeorological monitoring
more » ... tworks, a situation shared by much of the developing world, community-based monitoring can fill the observational void providing improved spatial and temporal characterisation of rainfall, river flow and groundwater levels. Such time series data are invaluable in water resource assessment and management, particularly where, as shown here, gridded rainfall datasets provide gross under or over estimations of rainfall and where groundwater level data are non-existent. Discussions with the local community during workshops held at the setup of the monitoring programme and since have demonstrated that the community have become engaged in the project and have benefited from a greater hydrological knowledge and sense of ownership of their resources. This increased understanding and empowerment is at the relevant scale required for effective community-based participatory management of shallow groundwater and river catchments.
doi:10.1016/j.jhydrol.2016.04.062 fatcat:ntjkx5zlhjdpfdlrof2tfivahi

Shallow groundwater in sub-Saharan Africa: neglected opportunity for sustainable intensification of small-scale agriculture?

John Gowing, Geoff Parkin, Nathan Forsythe, David Walker, Alemseged Tamiru Haile, Demis Alamirew
2016 Hydrology and Earth System Sciences Discussions  
There is a need for an evidence-based approach to identify how best to support development of groundwater for small scale irrigation in sub-Saharan Africa (SSA). We argue that it is important to focus this effort on shallow groundwater resources which are most likely to be used by poor rural communities in SSA. However, it is important to consider constraints, since shallow groundwater resources are likely to be vulnerable to over-exploitation and climatic variability. We examine here the
more » ... unities and constraints and draw upon evidence from Ethiopia. We present a methodology for assessing and interpreting available shallow groundwater resources and argue that participatory monitoring of local water resources is desirable and feasible. We consider possib le models for developing distributed small-scale irrigation and assess its technical feasibility. Because of power limits on water lifting and also because of available technology for well construction, groundwater at depths of 50 m or 60 m cannot be regarded as easily accessible for small-scale irrigation. We therefore adopt a working definition of shallow groundwater as < 20 m depth. <br><br> This detailed case study in the Dangila woreda in Ethiopia explores the feasibility of exploiting shallow groundwater for small-scale irrigation over a range of rainfall conditions. Variability of rainfall over the study period (9 % to 96 % probability of non-exceedance) does not translate into equivalent variability in groundwater levels and river baseflow. Groundwater levels, monitored by local communities, persist into the dry season to at least the end of December in most shallow wells, indicating that groundwater is available for irrigation use after the cessation of the wet season. Arguments historically put forward against the promotion of groundwater use for agriculture in SSA on the basis that aquifers are unproductive and irrigation will have unacceptable impacts on wetlands and other groundwater-dependent ecosystems appear exaggerated. It would be unwise to generalise from this case study to the whole of SSA, but useful insights into the wider issues are revealed by the case study approach. We believe there is a case for arguing that shallow groundwater in sub-Saharan Africa represents a neglected opportunity for sustainable intensification of small-scale agriculture.
doi:10.5194/hess-2015-549 fatcat:ow5kx6ser5fczkzhr3g2fc26f4

Africans in Yorkshire? The deepest-rooting clade of the Y phylogeny within an English genealogy

Turi E King, Emma J Parkin, Geoff Swinfield, Fulvio Cruciani, Rosaria Scozzari, Alexandra Rosa, Si-Keun Lim, Yali Xue, Chris Tyler-Smith, Mark A Jobling
2007 European Journal of Human Genetics  
DYS594, DYS617, DYS618, DYS636, DYS638, DYS640, DYS641 and DYS643) according to Lim et al. 17 and with an additional nine (DYS385a/b, DYS425, DYS426, DYS447, DYS448, Y-GATA-H4.1 and YCAIIa/b) according to Parkin  ... 
doi:10.1038/sj.ejhg.5201771 pmid:17245408 pmcid:PMC2590664 fatcat:56u55rx6azeapb46wvjr5kbpby

Mechanochemistry: opportunities for new and cleaner synthesis

Stuart L. James, Christopher J. Adams, Carsten Bolm, Dario Braga, Paul Collier, Tomislav Friščić, Fabrizia Grepioni, Kenneth D. M. Harris, Geoff Hyett, William Jones, Anke Krebs, James Mack (+6 others)
2012 Chemical Society Reviews  
2012) 'Mechanochemistry : opportunities for new and cleaner synthesis.', Chemical society reviews., 41 (1). pp. 413-447. Further information on publisher's website: The full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-profit purposes provided that: • a full bibliographic reference is made to the original source • a link is made to the metadata record in DRO •
more » ... e full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders. Please consult the full DRO policy for further details.
doi:10.1039/c1cs15171a pmid:21892512 fatcat:vjitko5hz5g73oyc2o6dqhf2l4

Seasonal patterns of rainfall and river isotopic chemistry in northern Amazonia (Guyana): From the headwater to the regional scale

Ryan Pereira, C. Isabella Bovolo, Nathan Forsythe, Nikolai Pedentchouk, Geoff Parkin, Thomas Wagner
2014 Journal of South American Earth Sciences  
We use first field-based observations of precipitation and river isotopic chemistry from a three-year study (2009e2011) in rainforest and nearby savannah in central Guyana at the northern rim of the Amazon rainforest to establish the quality of modelled or remotely-sensed datasets. Our 3 years of data capture a reduced rainfall regime in 2009 and an extended wet season in 2010, in contrast to the widely documented Amazonian floods in 2009 and droughts in 2010. Comparisons of observed
more » ... on with satellite derived TRMM and ECMWF ERA-Interim reanalysis precipitation show that both of these data sets capture the general pattern of seasonality, but substantially underestimate rainfall amounts in the primary wet season (by up to 50% and 72% respectively). The TRMM dataset is generally better at characterising the main dry season from September to December but the ERA-Interim model can overestimate precipitation in the dry season by up to 175%. Our new data on isotopic chemistry of river waters show that d 2 H/d 18 O values in this region are broadly consistent with interpolated global datasets of modelled precipitation isotopic signatures. The dominance of isotopically lighter water derived from the rains of the ITCZ during the wet season provides evidence of the close coupling of water chemistry of headwater rivers on the northern rim of Amazonia to the positioning of the ITCZ over the region. Our results highlight the challenge in understanding and representing local scale hydrological and biogeochemical characteristics using regional scale model data. We argue that combining point and local scale field data with larger scale model data is necessary to progress towards a comprehensive understanding of climateehydrology interactions in Amazonia. Crown
doi:10.1016/j.jsames.2014.02.005 fatcat:ljsr5xzt6fe23c5xpo5hmhfbcy

Mobilization of optically invisible dissolved organic matter in response to rainstorm events in a tropical forest headwater river

Ryan Pereira, C. Isabella Bovolo, Robert G. M. Spencer, Peter J. Hernes, Edward Tipping, Andrea Vieth-Hillebrand, Nikolai Pedentchouk, Nick A. Chappell, Geoff Parkin, Thomas Wagner
2014 Geophysical Research Letters  
We also thank Tim Eglinton, Geoff Abbott, and anonymous reviewers for constructive comments. The Editor thanks two anonymous reviewers for their assistance in evaluating this paper.  ... 
doi:10.1002/2013gl058658 fatcat:tywx6xnjo5bipi5wrxz6un2aje
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