Hydrological modelling using ensemble satellite rainfall estimates in a sparsely gauged river basin: The need for whole-ensemble calibration
Chris Skinner, Tim Bellerby, Helen Greatrex, and David Grimes.
Published in Journal of Hydrology, Volume 522, March 2015, 110-122
Read here (paywall) or free, non-formatted version here
This research highlighted some of the issues with using information from satellites to estimate how much rain has fallen over an area. Many satellite rainfall estimation methods cannot directly observe the rainfall itself, instead inferring the amount from other information, in this case the temperature of clouds – clouds cool whilst raining so if they are below a certain temperature it is likely they are raining. This method was pioneered by University of Reading’s TAMSAT team.
The relationship between cloud temperature and rainfall is not perfect and changes with distance and time, causing the rainfall estimates to be wrong in places. As we increase the detail we want to use the chances of it being wrong increase so to overcome this we can use lots and lots of repeat estimates – each using different relationships between cloud temperature and rain in different places and at different times – to create a set of results, each unique but with an equal likelihood of being correct.
This set of estimates can be used to run different types of models – for example, to run crop yield models to help us predict how well crops will have grown. For this research they were used to run a hydrological model to predict how much water will have flowed through a river basin. These models rely on us tuning values in them so that the outputs closely match observed values, a process called calibration, but when you have a set of different rainfall estimates for the same period which do you use to perform the calibration? The method that produced the best results was to use all of them together.
Why does it matter?
In the UK, our rainfall is monitored by a long-established and well-funded network of rain gauges and rain radar, providing us with a high detailed view of rainfall across the whole country in near real-time. This wealth of data helps us operate detailed forecasting systems to predict rainfall in the future and inform warning systems for drought and flooding. However, in many parts of the globe these networks to observe rainfall do not exist.
Across sub-Saharan Africa, including in the Senegal River Basin that provided the case study for this work, the lack of ground instrumentation is particularly acute. To fill the gaps in the data satellite information is used to estimate rainfall but this is not as accurate or as detailed as networks of ground instruments. These estimates are used to determine drought and flood warnings and by insurance companies that pay out to farmers who have lost crops, and consequently income, due to a lack of rain. It is important we understand fully what satellite estimates are telling us so we can make the correct decisions.
Why should you read it?
If you are interested in learning more about rainfall estimation is data-sparse regions and/or hydrological modelling using uncertain probabilistic input data.
Rainfall is a slippery thing. For those of us in the UK, we are very much aware that it can be raining one minute and then sunny the next, or it can be raining over your house but not over your friend’s house just a few streets away. This makes it a difficult thing to measure accurately and consequently meteorologists use several methods to try and do so.
The simplest way is to use a rain gauge. There are many different designs but, essentially, they are mostly all glorified buckets that fill with water as it rains, although some do take different approaches. They generally give us a good idea of how much rain has fallen at that spot between the times readings are taken. By automating the readings we can get a good idea of how the rainfall rate has changed over time.
Rain gauges cannot tell us how much rain has fallen outside the bucket. This is generally ok if you are still close to the bucket but the further away you get, the more of a problem this becomes. By using lots of rain gauges we can get a better idea of how the rainfall is varying across an area and we can use geostatistics to try and fill the gaps. However, the results will be different depending on the geostatistical method you decide to use.
Weather radar on the other hand is able to tell us the relative intensity of rainfall over an area. The radar sends out signals that are bounced back to it by rain and depending on the timing and strength of that signal we can tell where it is raining, and the areas it is heaviest. It does not directly measure the rain though and it needs calibrating against a reference point. This calibration may be less accurate as you move away from the reference point or if conditions change over time.
The consequence of this is the availability of different methods to measure rainfall, the results of which we call products. Each product will be different in its estimation of where, when, and how much rain has fallen and with many computer models of rivers relying on a measurement of rainfall as an input, the choice of product can have a big influence on the results from the model.
Landscape evolution models (LEMs) are designed to model changes to the Earth’s surface, usually over large areas and long time periods (at least one hundred years). Some of these models have become sophisticated and fast enough they can be used to explore more local and shorter-term changes. They need to use a rainfall product to run yet only rarely does a product exist that has a record long enough to cover the time scales simulated. Instead, we can use weather generators that take the characteristics of rain as recorded by a product to create long records of rainfall that are possible and likely based on the data.
In newly published led by EEI Research Fellow, Chris Skinner, a weather generator was used to produce long rainfall records based on different rainfall products, as well as a combination of information taken from each product. These synthetic records of rainfall were used to run a landscape evolution model for periods of 50 and 1500 years, finding that the patterns of erosion and deposition varied along a river depending on which product was initially used.
Due to the relationship between river flows and the movement of sediment in rivers, something known as the geomorphic multiplier, a small increase in river flow can result in a large increase in the amount of material eroded and transported by the river. This makes models of erosion and deposition extremely sensitive to changes in rainfall and consequently, the initial choice of rainfall product used can have a big influence on the model results.
As these modelling approaches are increasingly used to help understand the impacts of climate change or to help predict flood risk, understanding how the choice of rainfall product can impact results is crucial and needs to be properly managed by modellers.
We hope you are all keeping yourselves as safe as possible during the current period. We are very much missing being out and about and sharing our games and activities with everyone. To help share some of our work, Chris will be making short video tutorials and the first revisits the very beginnings of the SeriousGeoGames Lab and how we model the impacts sea level rise will have on flood risk.
The model used by Chris in the video is the Beta version of Humber in a Box (our first virtual reality activity) as used at Hull SciFest in 2014. The model code and data from this model were used by the developers to build into Unity-3D and add the beautiful, immersive, graphics. Sadly, Humber in a Box can no longer be used but you can get an idea of what it was like in the video below.
To go alongside the new tutorial, we are making the files for Humber in a Box Beta available so you can try it at home. It should run reasonably well on any modern PC. For a guide on how to get it running, skip to 10 minutes through the tutorial. Files can be downloaded from here.
Don’t forget to check out our previous post on how to use Flash Flood! from home too.
We find ourselves in difficult and testing times. We would love to be out there and sharing our games and virtual reality simulations with everyone but we at home doing the right thing. But, that doesn’t mean we cannot share some of games with you and we’ll be sharing these as we can.
Flash Flood! has been our flagship activity for many years and has seen several iterations. There are several ways you can enjoy it from home, the easiest being the 360 videos available on YouTube. These can be viewed on a Desktop, where you can navigate the direction of view using your mouse, but are best viewed on a Tablet or Phone (via the YouTube app NOT a browser) where you can change the direction of view by moving your device.
There are two versions. One with narration to guide you through –
And one with just sound effects intended for use in classes where someone will guide the group –
If you’re viewing on a phone and have a cardboard headset, click the google icon on the screen and place your phone into the headset for a VR-like experience.
Obviously, the best way to experience Flash Flood! is to play it. You can do this too by downloading the Desktop version. This was designed to work on a reasonably low spec of PC and can be operated with either an XBOX controller or just a keyboard and mouse.
Download the files from SourceForge here. If you have an XBOX controller choose FlashFloodDesktopInstall.exe and FlashFloodDesktopNoRadialsInstall.exe if you do not. Controls can be found in the Flash Flood Quick Start and Controls PDF document.
Whichever method you choose, the Living Manual (also in SourceForge) provides some background information, guidance for using it, and advice for using it in teaching. This document has not been updated for a while and we will be reviewing it in the next few days. We welcome submission of ideas of how to use these simulations to include in the Living Manual, if you’d like to contribute please contact us at seriousgeogames at hull dot ac dot uk.
We’d also love to hear your suggestions for content you’d like to see from us, feel free to ask and we’ll try our best. Keep yourselves safe and happy.
Freedom Festival is THE event in Hull. It all began in 2007 in celebration of the 200th anniversary of the abolition of the slave trade, an act passed after decades of work by Hull-born independent MP, William Wilberforce. Since 2007 it has grown massively, and in 2018 the festival had over 130,000 visitors.
“Excellent arts and culture can change lives and communities, by transmitting fundamental human values and inspiring all ages to embrace and celebrate freedom. We’ve seen it. It may be no surprise then that our ambition is founded on the legacy of Hull-born freedom advocate, William Wilberforce” – Freedom Festival website.
Chris demoing Humber in a Box at Freedom Festival 2015
SeriousGeoGames has been involved in three previous Freedom Festivals, starting in 2015 when we demoed Humber in a Box, and including 2016 when the virtual reality version of Flash Flood! was demoed to the public for the first time. With the Earth Arcade, we have the perfect opportunity to take things to the next level, and the Earth Arcade at Freedom Festival really will be something special.
The name Earth Arcade is meant to loosely evoke a sense of Arcadia – a mythical utopia where human society and the natural world live together in harmony. This is the future we hope for, the future we are striving to build, and we hope to inspire others to come with us on that journey. To create our mini-Arcadia we have teamed up with colleagues from the University’s School of the Arts to design the exhibit.
We will be exploring the impacts of the world’s most pressing environmental issues through our activities Flash Flood! Vol.2, Plastic Fishing, Top Trumps: Rivers, and small games on our Ipad stations. You will be able to find out how climate change and sea level rise will impact our city, Hull, and the wider Humber through our new and improved Rising Tide game on our big screen.
Freedom Festival will also see the debut of an exciting new activity space. The Forest is something a bit different to the rest of the Earth Arcade, and sci-comm in general. It is a quieter, reflective, and mindful space where people can sit and think about nature, with a small library of stories and ideas and crafts and workshops to inspire people to engage with nature more. We will be using theatrical and scenographic techniques to help people engage, such as interactive soundscapes.
Finally, we will be offering advice on how people can respond to the environmental issues explored, offering them the chance to sign up to becoming an Earth Arcade Champion by committing to making small changes in their own lives.
It is going to be brilliant and we hope to see you there!
I’ve been working on a prototype card game for SeriousGeoGames for a while now. The game, with the working title Resilience, sees players take control of a city and its surrounding area with the aim of staying in that job until the end of the game. The catch is there is another player with their own city also trying to reach that goal. With the ability to make events happen in each other’s cities, you each pose a threat to the other’s political survival.
Although I toyed with the idea of having multiple stresses to deal with, the game just got too unwieldy, so the focused down on flooding as the main hazard. Players can build defences, enact resilience measures, or implement things purely as they are popular – if they want to be aggressive, they can send a storm towards a rival city. Through playing the game, players will learn about the complexity of flood defence from physical, societal, and political perspectives.
360 time lapse of players trying an early version of Resilience at the EGU 18 Games Night.
The game is designed to be a deck builder, so rather than each having the same deck of cards players can choose a pile from their collection allowing them to try different strategies. I’m designing the game to have enough layers – through use of cards, dice, and tokens – that there will be numerous styles of play possible. The main goal of the design is for the game to be fun, with plenty of replay value, yet the deck building aspect adds in a further dimension – collectability.
I still have piles of Pokemon and Star Wars cards from when I was a kid, even though I never played either as a game. When I get free packs of cards in gaming magazines for games I will never play, I keep them. Especially the ‘shinies’. There is something tactile and attractive about a well-designed, crisp, high quality card, and this is something I want to tap into with Resilience.
My rubbish PowerPoint mock up (left), and Kelly’s design to use on the back of the cards (right). A big improvement!
Enter Kelly Stanford, Sci Artist. I’d been looking for an artist for a few months and seen some nice work, but no one seemed quite right for the game. Then I came across Kelly’s work on her Twitter and was blown away. She is a specialist in making science-based art and has worked on numerous public engagement projects, working in a range of styles from sculpture, hyper-realistic, and cartoon. She’s also a gamer and after a coffee meeting at the Manchester Museum of Science and Industry it was clear she got what I trying to achieve.
Here’s a some of my personal favourite artworks from 2018! 🎉 Thank you to everyone for the constant support + encouragement throughout the year and I hope you’ve enjoyed seeing my artworks as much as I’ve enjoyed making them! ❤️😊 #sciart#NewYearsEvepic.twitter.com/Bj1DmwjeKF
I commissioned her at the beginning of the year to develop the designs, and Kelly has wasted no time producing great designs for the cards – nothing like my rubbish PowerPoint efforts! So far we have the awesome logo for the back of the cards, a card template, and some concepts for the card types.
My original card template (left), Kelly’s template design (middle), and Kelly’s concept sketches.
I’m hoping to try out the first full prototype combining game and art designs at the EGU Games Night on April 10th, and after that I’m still not sure where it will go. There are several options to look at for production and dissemination, such as getting funding for a limited run, crowdfunding, getting a commercial backer, or simply releasing the game in a PDF to print your own cards. The game is designed so that additional decks can be added to the initial deck to add further complexity and variety, and I plan on offering bespoke limited edition shiny cards for events and projects.
I’m really excited about this project. I think the game has the potential to not only be fun but really help with the communication of flood risk management and its complexities and challenges. There is nothing quite like a game for putting you in someone else’s shoes. Keep an eye on this blog and Kelly’s blog for further news about Resilience.
We have had a fantastic and extremely busy 2018. Definite highlights have been the redevelopment of Flash Flood!, exhibiting in the Natural History Museum, and obviously, launching the Earth Arcade. In fact we have been so busy, we’re going to show you our highlights month-by-month.
We had over 80 school pupils from Newland St John’s visit us and try Flash Flood! and River in a Box as they learnt about flooding.
Our founder and SeriousGeoGamer, Chris Skinner, was awarded a University of Hull Research Excellency Award for Outstanding Impact, Outreach or Engagement, for his work with SeriousGeoGames.
In March we took Flash Flood! along to demonstrate at the Flood and Coast conference. We were part of a stand promoting our new home, the Energy and Environment Institute at the University of Hull.
The Energy and Environment Institute stand at Flood and Coast 2018.
2018 saw the first ever, unofficial, Games Day at the European Geoscience Union‘s General Assembly in Vienna, Austria. Chris Skinner convened a full science session sharing how researchers use games to research, teach, or share geosciences, and then in the evening over 200 scientists came together to play the games.
Promotional image made for the EGU Games Day 2018.
Articles featuring Flash Flood! were published in Teaching Geography and Geographical Review magazines.
In May we started putting together the kit and branding for the Earth Arcade, and its fist outing was supporting a visit of a delegation from the New Partnership for Africa’s Development (NEPAD). We even featured on the front page of their newsletter.
Chris Skinner demonstrating the Earth Arcade interactive touchtable.
The kit we put together includes five full VR stations and a large interactive touchscreen table.
Later in the month we spoke to over 500 members of the public at the Natural History Museum, as we were joined by colleagues from the University of Reading to demonstrate Flash Flood!. The event was part of the Museum’s half-term programme supporting NERC’s Operation Earth.
Demonstrating Flash Flood! at the Natural History Museum.
Chris Skinner shared Flash Flood! at the Natural History Museum with a Nature Live talk.
We were invited to participate in the Living with Water project’s Hulltimate Challenge event, and we took a copy of Flash Flood! down to Queen Victoria Square, central Hull, to support the press launch of the event. This was the first time we used the branded Earth Arcade kit in public.
We launched the Earth Arcade officially to colleagues within the University of Hull with an event held in the Map Library of the Cohen Building.
Setting up the Earth Arcade branding for the first time in the Map Library.
In September things got really busy! We started by once again teaming up with BetaJester to redevelop Flash Flood! for our new Earth Arcade kit – Vol.2 features sound effects, voice overs, improved graphics, and greater realism.
As part of the British Science Festival, hosted at the University of Hull, we took three activities down to Humber Street for an evening science street party. We demoed Flash Flood!, Humber in a Box, and our touchscreen table.
Earth Arcade assets at the British Science Festival.
At the Hull Science Festival we officially launched the Earth Arcade to the public and exhibited a mini-festival within the festival itself. In our Earth Arcade we showed the Flash Flood! Vol.2 for the first time, Plastic Ocean Fishing, Flood City – Hull, Humber in a Box, and a collection of Top Trump card games.
The first ever Earth Arcade at Hull Science Festival.
For the second time we were nominated for the HEY Digital Award for Best Use of Technology in Education, but lost out to the excellent Ron Dearing UTC.
We collaborated with colleagues across the University to use our games and research to help with teaching students, including assisting with modules in Drama, Digital Media, and Computer Science.
A delegation of flood risk practitioners from Sweden were visiting Hull to learn from the local City Council and the Living with Water project. We were invited to share Flash Flood! Vol.2 with them, and even got a tour of the Hull Tidal Barrier.
At the end of the month, Chris Skinner spoke to over 50 City of Culture volunteers about the University of Hull’s research into plastic pollution and the #MyPlasticPledge project as part of a masterclass for the launch of the Hull Refill scheme.
The big event of October was the Living with Water’s Hulltimate Challenge – a huge 10 km assault course around the centre of Hull. The Earth Arcade was a sponsor, we exhibited Flash Flood Vol.2 and Ocean Plastic Fishing, and large team from the Energy and Environment Institute successfully completed the course.
Team EEI and the Earth Arcade at the Hulltimate Challenge.
We were invited to bring the Earth Arcade to the Manchester Science Festival via a Platform for Investigation at the Manchester Museum of Science and Industry. This was our first ever plastic pollution focused event.
PI – The Problem with Plastics at Manchester Science Festival.
The University of Hull stand at Scarborough Science and Engineering Week won an award for Most Informative Exhibit, and we were pleased to be part of this stand with Flash Flood! Vol.2.
November saw Flash Flood! come home. The original Flash Flood! was produced for and funded by the NERC Flooding from Intense Rainfall (FFIR) research programme, and with the programme coming to a conclusion we were invited to provide a Games Room at the final showcase for the event at the Royal Society, London. We brought along the full set of Flash Flood Vol.2, Flood City – Hull, and were joined by games from University of Reading and Sam Illingworth of Manchester Metropolitan University.
Exhibits and the Earth Arcade at the NERC-FFIR Showcase.
The final public event of the year for us was using Flash Flood! Vol.2 to promote the Energy and Environment Institute at the Scarborough Business Day, where the keynote speaker was former Deputy Prime Minister, Lord John Prescott.
The EEI stand at Scarborough Business Day
We ended the year as we begun with a visit from pupils from local schools who used Flash Flood! Vol.2 as part of a workshop looking at flooding and geomorphology.
Finally, we were part of a team including #MyPlasticPledge and Kids Against Plastic looking at how we can all reduce the amount of plastic waste we produce at Christmas, with the 12 Days if Plastic-free Christmas.
2019 promises to be an equally busy and exciting year and will see the development of new games, including Inundation Street (an urban-based VR flood simulator), and Resilience (a collectible card game). It is also sad as we say farewell and good luck to SeriousGeoGame veteran, Chloe Morris, as she travels to Australia to start the next stage of her career – we will miss you Chloe!
Good bye Chloe… 🙁
Thank you everybody who has supported us in 2018, and a special thank you to all the volunteers who have helped us bring our games to the public – we really couldn’t do it without you.
Would it even be Christmas if you weren’t subjected to endless repeats? Christmas repeats are good though – it doesn’t matter if you’ve seen it hundreds of times the sight of Del Boy and Rodney saving the day dressed as Batman and Robin is still funny 22 years on. That’s why we are bringing you a repeat of the 12 Days of Plastic-free Christmas.
The 12 Days of Plastic-free Christmas was produced by a partnership between Earth Arcade, #MyPlasticPledge, and the Energy and Environment Institute at the University of Hull, with special contributions from Kids Against Plastic and Kate Smith. Each day we looked at a small part of Christmas, highlighted some of the plastic related issues with it, and suggested a quick, easy, and cheap way to reduce that impact. You can see each post by clicking the links below.
There is a surprising amount of plastic in wrapping paper, from labels, ribbon and glitter, to plastic infused with the paper itself. How can you be sure it’s plastic-free? Try the scrunch test or make your own.
Lucie tells us all about the plastic in wrapping paper.
Finally, the big day, and the wonderful Christmas Dinner – Turkey, potatoes, pigs-in-blankets, sprouts, and piles and piles of plastic packaging and waste. make your own canvas bag and buy loose vegetables to keep your waste to a minimum.
So that was our 12 Days of Plastic-free Christmas. If you have tried one of tips, we would love to see your efforts – feel free to share them with us either here, on our Facebook, Instagram, or Twitter.
Thank you to all who helped and contributed – Katie Parsons, Kate Smith, Flo Halstead, Freija Mendrick, Phil Bell-Young, Chris Skinner, the Meek family, Lucie Parsons, Dan Parsons, Hannah Lightley, Ellie Bartle, and Kat Sanders.
We are super-super-super excited to tell you we will be bringing our Flash Flood! VR game to the Natural History Museum in London. We will be joining a series of other exhibits as part of the Museum’s half-term Operation Earth showcase, and we will be there from the 29th of May until the 31st of May, 11am to 4pm each day. To find out more about this event, click here.
In the last couple of years we have been at the Science Showcases for the Natural Environment Research Council (NERC) – Into the Blue and Unearthed. This year, NERC are doing something a little different, working with museums and science centres to bring their Operation Earth family science show to people up and down the country. To learn more about Operation Earth and to find an event near you, click here.
We are also very excited that we’ll be joined by our friends from the University of Reading, and the NERC-funded Flooding from Intense Rainfall project (FFIR) – the project for which Flash Flood! was designed. At the event you can play Flash Flood! and meet the scientists whose research inspired it, both from Reading but also the Energy and Environment Institute (EEI) at the University of Hull.
SeriousGeoGames will be supporting the Geoscience Games Night, both by providing the drinks (free beer!) and bringing along some of our games and will be debuting our prototype deck-builder card game, Flood: Attack & Defend. Below you will find a list of the games we know people are bringing, but do feel free to bring your own along too. Let us know if you’re bringing a game and we’ll add it to the list.