tag:theconversation.com,2011:/institutions/politecnico-di-bari-2535/articlesPolitecnico di Bari2018-07-12T22:14:38Ztag:theconversation.com,2011:article/992682018-07-12T22:14:38Z2018-07-12T22:14:38ZCómo las imágenes por satélite pueden mejorar la eficiencia energética de nuestras ciudades<figure><img src="https://images.theconversation.com/files/226926/original/file-20180710-70039-162rs9g.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">FOTO ARTICOLO LandViewer</span> </figcaption></figure><p>Las cosas no son lo que parecen. Si no fuera por la posición del sol en la esquina superior derecha, podría parecer que las imágenes situadas bajo estas líneas se hicieron en dos momentos diferentes del día: por la mañana la de la izquierda y al atardecer la de la derecha. En realidad, ambas fueron tomadas a las 11:10 con un intervalo de pocos segundos. La única diferencia es que, en la segunda, se utilizó a modo de filtro la lente polarizada de unas gafas de sol.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/226680/original/file-20180709-122250-lcqjti.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/226680/original/file-20180709-122250-lcqjti.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/226680/original/file-20180709-122250-lcqjti.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=257&fit=crop&dpr=1 600w, https://images.theconversation.com/files/226680/original/file-20180709-122250-lcqjti.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=257&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/226680/original/file-20180709-122250-lcqjti.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=257&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/226680/original/file-20180709-122250-lcqjti.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=323&fit=crop&dpr=1 754w, https://images.theconversation.com/files/226680/original/file-20180709-122250-lcqjti.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=323&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/226680/original/file-20180709-122250-lcqjti.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=323&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Figuras 1 y 2.</span>
<span class="attribution"><span class="source">Autores</span></span>
</figcaption>
</figure>
<p>Este curioso ejemplo nos recuerda que el ser humano percibe solo la radiación visible. Por eso no es capaz de apreciar otros fenómenos que ocurren a su alrededor, que tienen lugar en la llamada ventana óptica del espectro electromagnético, la parte izquierda del siguiente gráfico:</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/226687/original/file-20180709-122253-1d4qhr6.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/226687/original/file-20180709-122253-1d4qhr6.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/226687/original/file-20180709-122253-1d4qhr6.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=427&fit=crop&dpr=1 600w, https://images.theconversation.com/files/226687/original/file-20180709-122253-1d4qhr6.PNG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=427&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/226687/original/file-20180709-122253-1d4qhr6.PNG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=427&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/226687/original/file-20180709-122253-1d4qhr6.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=537&fit=crop&dpr=1 754w, https://images.theconversation.com/files/226687/original/file-20180709-122253-1d4qhr6.PNG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=537&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/226687/original/file-20180709-122253-1d4qhr6.PNG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=537&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Figura 3.</span>
<span class="attribution"><span class="source">Vivancos, J. et al. (2006). La Tierra a vista de satélite. http://concurso.cnice.mec.es/cnice2006/material121/</span></span>
</figcaption>
</figure>
<p>Para entender mejor nuestra manera de ver las cosas, cojamos unas imágenes del satélite Landsat 8 de la NASA. En la fotografía de abajo a la izquierda podemos apreciar, en el espectro visible, una forma rectangular que recuerda a un parque. En la de la derecha vemos la misma zona, pero en este caso se muestra información procedente de una radiación que no podemos percibir de manera natural con nuestros ojos. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/226689/original/file-20180709-122265-1uwtumb.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/226689/original/file-20180709-122265-1uwtumb.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/226689/original/file-20180709-122265-1uwtumb.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=225&fit=crop&dpr=1 600w, https://images.theconversation.com/files/226689/original/file-20180709-122265-1uwtumb.PNG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=225&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/226689/original/file-20180709-122265-1uwtumb.PNG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=225&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/226689/original/file-20180709-122265-1uwtumb.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=283&fit=crop&dpr=1 754w, https://images.theconversation.com/files/226689/original/file-20180709-122265-1uwtumb.PNG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=283&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/226689/original/file-20180709-122265-1uwtumb.PNG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=283&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Figuras 4 y 5.</span>
<span class="attribution"><span class="source">EarthExplorer de la NASA. (2018). https://earthexplorer.usgs.gov/</span></span>
</figcaption>
</figure>
<p>¿Qué es lo que estamos viendo? La respuesta es sencilla: no es más que una balsa de tratamiento de aguas residuales en donde el color rojo brillante nos indica los sólidos que están en suspensión en el líquido.</p>
<p>En la actualidad, las imágenes procedentes de los satélites que orbitan la Tierra nos permiten obtener una gran cantidad de información. Solo hay que saber cuál es la combinación correcta de las bandas del espectro proporcionadas por el sensor. También la influencia del clima, como la temperatura y la precipitaciones, en la fiabilidad de los datos extraídos de cada píxel. Así podremos obtener los algoritmos necesarios para estudiar lo que queramos.</p>
<p>Por ejemplo, para obtener la eficiencia energética de un edificio mediante imágenes satélites. A partir de las variables obtenidas mediante plataformas de acceso libre <a href="http://landsatexplorer.esri.com/">de la NASA</a> y de la <a href="https://www.esa.int/esl/ESA_in_your_country/Spain">Agencia Espacial Europea (ESA)</a>, se han desarrollado una serie de modelos zonales que permiten obtener la temperatura del edificio y su energía primaria y total. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/226837/original/file-20180709-122274-1ru0n6k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/226837/original/file-20180709-122274-1ru0n6k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/226837/original/file-20180709-122274-1ru0n6k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=370&fit=crop&dpr=1 600w, https://images.theconversation.com/files/226837/original/file-20180709-122274-1ru0n6k.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=370&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/226837/original/file-20180709-122274-1ru0n6k.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=370&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/226837/original/file-20180709-122274-1ru0n6k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=465&fit=crop&dpr=1 754w, https://images.theconversation.com/files/226837/original/file-20180709-122274-1ru0n6k.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=465&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/226837/original/file-20180709-122274-1ru0n6k.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=465&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Figura 6.</span>
<span class="attribution"><span class="source">NASA y Esri. (2018). Visor Landsat Explorer. http://landsatexplorer.esri.com/</span></span>
</figcaption>
</figure>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/226838/original/file-20180709-122253-1541vf2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/226838/original/file-20180709-122253-1541vf2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/226838/original/file-20180709-122253-1541vf2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=428&fit=crop&dpr=1 600w, https://images.theconversation.com/files/226838/original/file-20180709-122253-1541vf2.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=428&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/226838/original/file-20180709-122253-1541vf2.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=428&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/226838/original/file-20180709-122253-1541vf2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=538&fit=crop&dpr=1 754w, https://images.theconversation.com/files/226838/original/file-20180709-122253-1541vf2.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=538&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/226838/original/file-20180709-122253-1541vf2.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=538&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Figura 7.</span>
<span class="attribution"><span class="source">EOS platform. (2018). Land Viewer. https://eos.com/landviewer/</span></span>
</figcaption>
</figure>
<p>Más tarde, a través del análisis de gran cantidad de datos (<em>big data</em>), se pueden conseguir parámetros de sostenibilidad del área urbana. Por ejemplo, la superficie de área verde y la relación entre esta y el área construida.</p>
<p>Una de las características de los modelos basados en el tratamiento digital de imágenes tomadas por satélite es que se basan en el análisis de <em>big data</em> a nivel de macroescala (por ejemplo, una ciudad o barrio). </p>
<p>Posteriormente, mediante el uso de variables zonales como la superficie edificada, superficie verde, temperatura y precipitación, se obtienen resultados a nivel de microescala (por ejemplo, un edificio).</p>
<p>Los beneficios de esta nueva tecnología, que hemos probado con éxito en la ciudad italiana de Bari, van desde la facilidad de obtención de los datos en cualquier parte del mundo y el ahorro económico en el proceso de toma de datos a la rapidez del proceso y la precisión de los datos y los resultados obtenidos. </p>
<h2>Una solución verde</h2>
<p>No podemos olvidar que, a consecuencia del mundo globalizado en el que vivimos, el desarrollo sostenible de nuestras ciudades y barrios depende de la superficie verde por habitante. Otros parámetros que influyen en la eficiencia energética global son el uso de la bici, del transporte público y la peatonalización de calles y avenidas.</p>
<p>Por eso es importante señalar que este sistema permite gestionar grandes áreas de trabajo sin repercutir negativamente en el medio ambiente. Además, el uso de satélites permite analizar aquellas áreas en las que es necesario implementar planes de actuación por parte de las autoridades locales. Así será posible aumentar las zonas verdes y minimizar las necesidades energéticas de la ciudad, disminuyendo el gasto de sus habitantes.</p><img src="https://counter.theconversation.com/content/99268/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Emilio Ramírez Juidías Trabaja para la Universidad de Sevilla (España)</span></em></p><p class="fine-print"><em><span>Lucia Garzone no recibe salario, ni ejerce labores de consultoría, ni posee acciones, ni recibe financiación de ninguna compañía u organización que pueda obtener beneficio de este artículo, y ha declarado carecer de vínculos relevantes más allá del cargo académico citado.</span></em></p>Las imágenes satelitales ofrecen información valiosa para mejorar la eficiencia energética y suponen ahorro económico en un proceso rápido y preciso.Emilio Ramírez Juidías, Remote sensing applied to environment, Advanced industrial design, Archaeology (VR/AR), Solar physic, Universidad de SevillaLucia Garzone, Investigadora en Efficiencia Energetica en Arquitectura, Politecnico di BariLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/559812016-03-10T13:30:19Z2016-03-10T13:30:19ZModern buildings have an alarming flaw when people need to escape quickly<figure><img src="https://images.theconversation.com/files/114334/original/image-20160308-22123-170n80u.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">How best to get out?</span> <span class="attribution"><a class="source" href="http://www.shutterstock.com/cat.mhtml?lang=en&language=en&ref_site=photo&search_source=search_form&version=llv1&anyorall=all&safesearch=1&use_local_boost=1&autocomplete_id=&searchterm=evacuate&show_color_wheel=1&orient=&commercial_ok=&media_type=images&search_cat=&searchtermx=&photographer_name=&people_gender=&people_age=&people_ethnicity=&people_number=&color=&page=1&inline=261647225">Ambrozinio</a></span></figcaption></figure><p>The landscapes in which many of us live would have been unimaginable to previous generations. We now have skyscrapers so striking and tall they would make <a href="http://www.greekmyths-greekmythology.com/myth-of-daedalus-and-icarus/">Icarus</a> turn pale. Yet in emergency situations, our seemingly brilliant designs sometimes turn against us – and become death traps when disaster strikes. </p>
<p>Safety engineering is about designing buildings that reduce the negative effects of accidents and attacks. The basic concept is straightforward: it takes a while after an incident before a structure collapses. If you can design it so that the time for everyone to flee is shorter than the time it takes to collapse, you save lives. This is the standard approach for big or complex structures in many countries, including the UK, US, Japan, Sweden and Italy. </p>
<p>But how long does it take to evacuate a building? It depends on the building and the escape routes, but crucially also on how people behave. To estimate the time it would take for everyone to flee – the “egress time” as we call it – safety engineers use computer simulations in which people evacuate after an incident and react to whatever happens around them. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/114304/original/image-20160308-22114-fjzc4k.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/114304/original/image-20160308-22114-fjzc4k.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/114304/original/image-20160308-22114-fjzc4k.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=314&fit=crop&dpr=1 600w, https://images.theconversation.com/files/114304/original/image-20160308-22114-fjzc4k.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=314&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/114304/original/image-20160308-22114-fjzc4k.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=314&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/114304/original/image-20160308-22114-fjzc4k.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=395&fit=crop&dpr=1 754w, https://images.theconversation.com/files/114304/original/image-20160308-22114-fjzc4k.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=395&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/114304/original/image-20160308-22114-fjzc4k.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=395&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Simulation of a fire evacuation in an underground station.</span>
<span class="attribution"><span class="source">Ruggiero Lovreglio</span></span>
</figcaption>
</figure>
<p>The problem is that the simulations aren’t good enough – that’s <a href="http://link.springer.com/article/10.1007/s10694-015-0501-2">what we have learned</a> from detailed behavioural studies based on recent fires and terrorist attacks including 9/11 and the Mont Blanc <a href="http://www.telegraph.co.uk/news/worldnews/europe/1374139/Toll-of-tragedies-continues-to-rise-despite-mans-best-efforts.html">tunnel fire</a> of 1999 in which 41 people died. So either we teach evacuees to behave like our models – or, more realistically, improve our models. </p>
<p>This is not easy because the evacuee will make a host of different decisions: whether and when to start moving, in which direction, whether to respond to other evacuees, and which exit to use. Each choice also depends on how various factors interact with one another. Is the decision maker bold or risk-averse? Is there smoke in the room? How far away are the exits? And of most interest for our research purposes, what are the other evacuees doing?</p>
<h2>Seen and then herd</h2>
<p>We have all seen what sometimes happens with pedestrians at a red traffic light. Everybody quietly waits for the green light until someone decides to cross early, and then suddenly the whole group copies them. We call this “herding behaviour” – and when it comes to evacuation, it can be dangerous. It can create excessive congestion at some exits, increasing the all-important amount of time it takes for everyone to flee. </p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/114340/original/image-20160308-22135-18h9nnq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/114340/original/image-20160308-22135-18h9nnq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/114340/original/image-20160308-22135-18h9nnq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=736&fit=crop&dpr=1 600w, https://images.theconversation.com/files/114340/original/image-20160308-22135-18h9nnq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=736&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/114340/original/image-20160308-22135-18h9nnq.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=736&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/114340/original/image-20160308-22135-18h9nnq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=925&fit=crop&dpr=1 754w, https://images.theconversation.com/files/114340/original/image-20160308-22135-18h9nnq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=925&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/114340/original/image-20160308-22135-18h9nnq.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=925&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Groupthink.</span>
<span class="attribution"><a class="source" href="http://www.shutterstock.com/cat.mhtml?lang=en&language=en&ref_site=photo&search_source=search_form&version=llv1&anyorall=all&safesearch=1&use_local_boost=1&autocomplete_id=&search_tracking_id=8tKDmriPFKvw63_oawXpeA&searchterm=herd%20mentality&show_color_wheel=1&orient=&commercial_ok=&media_type=images&search_cat=&searchtermx=&photographer_name=&people_gender=&people_age=&people_ethnicity=&people_number=&color=&page=1&inline=128046740">JSlavy</a></span>
</figcaption>
</figure>
<p>Herding used to have a bad name among evacuation scholars. It is an irrational consequence of panic, we <a href="https://www.researchgate.net/publication/224010870_Simulation_of_pedestrian_crowds_in_normal_and_evacuation_situations">used to say</a> – the more evacuees panic, the more they herd. And of course it is difficult to design structures that take account of irrationality. But we showed in a <a href="http://www.sciencedirect.com/science/article/pii/S0925753515002763">recent study</a> that it can be perfectly rational to copy the behaviour of other evacuees. And if herding is actually what people do in an emergency, it is not something to fight but something to understand and possibly exploit. Panic was being made a scapegoat for tragedies that were partly avoidable. </p>
<p>The purpose of our study was to look at how common herding is in an emergency situation. To do this, we set up a choice experiment online. We created a few realistic videos with different emergency situations, in each case offering decision makers a series of choices between two doors. We invited people around the world to participate, and ended up with more than 1,500 participants. This was a big improvement on <a href="http://www.sciencedirect.com/science/article/pii/S0925753513002294">previous studies</a> in which we have been involved, which offered far fewer choices and involved fewer than 200 respondents. </p>
<p>We found that in an emergency, if an evacuee is faced with two doors and no one else is around, they are as likely to choose one door as the other. If you put a few other evacuees close to one of the doors, however, some of the other evacuees will follow them – instead of worrying that those people might slow down their escape. According to our analysis, the sight of ten people close to a door may be roughly as persuasive to these people as seeing an “exit” sign hanging on it. </p>
<p>The point is that if herding is the human norm, safety engineers need to start taking it into consideration. It is not as easy as saying that this or that disaster could have been avoided if we considered herding, but we need to build it into our simulators and then use the insight to make buildings that are safer in emergencies. One option might be to provide evacuees with real-time information, for instance, such as with dynamic signage systems of the kind that <a href="https://youtu.be/kbVT5OZfMF4">have been tested</a> in Barcelona. </p>
<p>But first we have to understand what kind of people are more prone to trust the decisions of other evacuees, and also how herding affects other evacuation choices such as the decision to start evacuating. Suffice to say, for now there is a major problem with the way we evaluate the safety of the structures in which we live and work. Until we address it, our chances of survival are a little like those of the characters from Greek legend – in the lap of the gods.</p><img src="https://counter.theconversation.com/content/55981/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>The authors do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Getting out in a crisis is often harder than it looks. But science can help.Ruggiero Lovreglio, Pre-doctoral researcher, Politecnico di BariAchille Fonzone, Lecturer in Transport Modelling, Edinburgh Napier UniversityLicensed as Creative Commons – attribution, no derivatives.