to surprise a trick you ask up and get our. interview on d w. what secrets lie behind. discover new adventures in 360 degree. and explore a major world heritage sites cuckoo world heritage 363 get me up now. oh blue planets is becoming increasingly dominated by concrete over half of the global population now lives in cities and the number is rising. not only are millions of people moving into urban areas wild animals are entire populations of them. open areas are covered in cement bricks and asphalt which in hot weather turns them into hot spots literally. and that's

a good look at the rising temperatures in the us cities welcome to tomorrow today the science show on t.w. . the northern hemisphere is the 2nd hottest summer since records began and is just coming to an end. in the last 140 years there's only been one some a hotter than this 12016 that's here august was particularly roasting the fall of hottest summers were all in the last 5 years climate change is catching up with us it's particularly evident in cities because they become heat ivan's. help and heating is the name given to the so-called heat island effect temperatures and towns and cities rise more sharply than in the surrounding areas because of the density of streets and buildings and the. many people cars and trains all of which

produce heat. spread over the year the mean air temperature in areas is around $1.00 to $3.00 degrees celsius warmer than areas outside and only spaces within them. on top of this town and city centers often cool down fall less at night because the buildings density doesn't allow cool air to move around the city. on hot summer nights without a green the temperature difference between a city and its surroundings can be more than 10 degrees celsius. what's needed is cool air from the surrounding area but what happens when a current of air meets an obstacle that's what under us will be missed researching with the help of water light shining on tiny white particles suspended in the water reveals currents in the tank. here the current flows unhindered

but then it hits a building. you can see there in front of it that there's turbulence and that current flows over the top of the building and there's more turbulence behind it this is what happens when an air current is confronted with a building this is just one building but in a city that there are lots of them and that means that all kinds of air currents. does cold air flow over a building or around it and what happens if there were obstacles in its path he factors in blocking the flow of air. the bigger it is the more the current is blocked or. if i add another obstacle behind the 1st one that creates an area between them that is poorly ventilated. removed the wind if it only comes from the front goes over the top of both buildings. in the area between them remains poorly

ventilated. but you can reduce this effect if you place the building with its narrow side facing the wind. that reduces the surface area the wind hits and allows it to flow past all the building. with. urban planners need to pay close attention to the orientation of buildings relative to prevailing winds here for example they block cool air coming off the high ground into the valley but if they're turned to 90 degrees the wind passes between them and everything gets nicely ventilated. high rise buildings can also do their part in ventilating a city. although if i place a tall building behind a short one. when it goes over the top of the short one and blows down into the

street in front of the tall swirls around. you can influence the exchange of air in a city quite well pending on where the building stand relative to each other. if a tall building is right in front of the short one that blocks the breeze and prevents the distance is great enough the current also reaches the short going. big gaps between city buildings are rare this proximity makes them he said and some cities like chennai and mumbai in india can reach temperatures of. lagos in nigeria is also one of the world's hottest cities. as is mecca in saudi arabia. and he's saying is happening across the globe even in cooler places like the german capital of them. jerk funk

is an urban climate expert searching for effective ways to reduce city temperatures this detailed model of berlin is going to help him. in hot weather the german capital is an urban heat island thermal imaging shows how populated urban areas function like hot plates they can be up to 8 degrees warmer than outlying areas. the researcher is using this mini world to find a solution. inside this model of a city apartment and ice cube will demonstrate how much heat gets through. the test houses made of regular building materials. to see what happens when the sun shines on a brick building the building warms up and what happens if we use other materials

insulate the facade of or if we put a tree in front of it. using time lapse imaging we can see how people fare in this kind of building it only takes half. an hour for the house to really heat up very soon they would be practically melting in the heat and no wonder it's over 30 degrees. buildings as we've reproduced them here in the model absolve the heat energy of the sun very well and stoled its energy very well. this is due to the albi to affect with the color of a building material dictates how much radiation from the sun is reflected by its surfaces. in the case of blank slate for example the all below value is 0 point one that means just 10 percent of the rays from the surface are reflected. with reg roof tiles the values between 0 point

one and 0.35 and with white facades like the ones common increase the i'll beat 0 value is between 0.5 in 0.9 the lower the value of their for solids or roofs the hotter the buildings in the city will be. now the expert tries simple countermeasures 1st external thermal insulation panels . if we want to see what effect this has on the building ultimately insulating the facade not only ensures that he stays in the. it also keeps heat out of the apartment. next comes a coat of light colored paint this reflects the sunlight and so keeps the heat out . brightly painted and insulated the house then gets

a layer of greenery on its roof before being bathed in another half hour of 1000 watt sunshine a couple of shade providing trees round off the protective measures. when behold this time our hypothermic resident. it's still on its feet no wonder with an interior temperature of almost $23.00 degrees. since now about $23.00 degrees in the apartment and compared to the temperature of around 30 degrees at the start of our experiment that's a big drop in the world. which all goes to show that paint can play an important role in easing the city's he problem. has canned green spaces in a city. and they don't only offer a fresh mint. it's a paradox while the habitat of wild animals shrinks thanks to expanding cities some

creatures are fleeing to urban areas and finding refuge in them. even develop into unique groups of city developing animals. urban foxes live among us but make only occasional fleeting appearances there are a growing presence in cities and have proven to be highly adaptable. evolutionary biologist sophia q make researchers berman's fox population for wild animals the city is a challenging habitat. among my bidding you have to bear in mind what sort of a habitat the city is it's such an artificial environment and there's so much manmade imposed that foxes have to withstand the light and noise traffic i find that fascinating to me and. to me has been gathering data on urban foxes for the

last 5 years she's equipped 17 of them with a transmitter that allows her to track their movements she's also set up cameras near foxholes in order to monitor the activities of their inhabitants. and women must also at the moment i'm trying to find out if they're actually hit. i know they're in the area but it's a wide area there are lots of folks than and i'd like to know which one they're actually using on the moment but let's not. kill it is writing a doctoral thesis at the lab which institute for zoo and wildlife research on the behavioral ecology of red foxes in urban environments. she cited specimens in parks and even in berlin's government district. yet none of the strong smell indicates fox is off and some are. there goes a rabbit. as we can see there are rich pickings for foxes here and he's also.

one of the foxes sophia kimock has located is beneath containers at the edge of a park the foxes keep a low profile during the day but they did leave traces of the monkey know him but if you look closely you can see a footprint up book. urban foxes live in close proximity to the human population how come given that they're naturally shy animals. well they found a habitat in the city where no one is preying upon them as is the case in the countryside whether many food sources for on of all those folks is a highly opportunistic and the anything they find although they're especially good at hunting mice and other rodents they can also live off rotting fruit. and all sorts of things really. there is no shortage of trash in the city

it's one big buffet as far as the foxes are concerned. berlin is believed to be home to between 5010000 foxes fox cubs born in the city are unfazed by the hustle and bustle of the big city. foxes are becoming ever less timid. sophia q makes research has revealed that berlin has its own indigenous population and the animals are in fact genetically different from their country cousins. stock kinds of time and again schools of the city limits seem to mark about area between fox population was still leave me between the city and the countryside but it's massively reduced. the forces that live in the city you don't want to leave it to you and cox's that live in the countryside don't want to venture into the city. because they're afraid they're not used to being close to humans in your defense and. her research has also shown that urban foxes mark out their territory and

like to stay in it with some exceptions. then he took his reach maturity and also him and starts to migrate to the territory so they make their way through the city and you think they would choose to travel through the parks green spaces but in fact they tend to travel along the most ways to get from one place to the next. foxes obviously appreciate the benefits of urban infrastructure they're becoming increasingly bold urban foxes often even approach humans. to the consternation of many foxes are thought to carry disease although in fact release was a radical idea in germany in 2008 and. which is highly dangerous is rare. have been having our mission of western dutch on this knife. and it's rare across

germany and the risk of getting infected is very very now to fix and if you don't come into direct contact with fox's then you're not at risk and in general you just stick to hygiene rules often working in the garden if you've been taking in the soil but he didn't even add up. anywhere where foxes might lurk where there's fallen fruit vegetables or berries it's important to keep washing your hands and if you do encounter a fox keep your distance. most berliners don't mind living in close proximity to foxes info. they like them sophia kimock will be completing her ph d. thesis this year her research our urban populations has been exhaustive she's grown fond of her bushy tailed research subjects. here that's better folks and where is where the 2nd fox i can't without trying. a

tough cookie who read how young here every year. i don't get any data from her anymore but i still come by to see if she's still here to check up on her up so here are a few urban foxes live to a ripe old age in the city field goals are their greatest enemy yet the growing presence of foxes shows that the opportunities of city life clearly outweigh the threats. and yet suppose that he's continued to sprout up at an alarming rate eating ever more into surrounding areas humans and their beloved countries are taking over like here in china. and here in cutter. as a consequence animals and humans are getting closer to even sharing diseases but this retreat from india had a question about that. what is it were not take diseases they are

diseases caused by pathogens carried by non-human animals that spread to people. out of every 10 infectious diseases are believed to be 0 and are sick. the pathogens can be viruses bacteria parasites all funky many of the diseases they cause in people a mild but some a serious and even deadly. the bubonic plague tuberculosis malaria and ebola as. an arctic diseases that have killed countless millions of people. musky toes and caps. but also cats and dogs and many other species carry pathogens that can make people sick but often they don't make the animals that host them sick transmission can occur via a bite also eating the flesh of a carrier or contact with its blood or feces. zylon

arctic diseases can spread fast and far if the pathogens adapt to be transmitted from person to person that's the case with the novel coronavirus. one hypothesis is that pangolin so the intermediaries that transported the novel coronavirus from its natural hosts pass to humans. what markets where life wild animals are sold are considered a potential site of transmission of zoo in arctic disease pathogens some have been closed for that reason. infectious diseases from animals are a growing problem the problem has to do with humans encroaching on animal habitats forests are cleared for timber or to make space for farms or towns humans and animals species are no longer far apart this office opportunities for the pathogens to make the leap. there are more than $200.00 known

zoonotic diseases the wreck countless germs out there to which humans have no immunity on new devastating diseases lurking to prevent the making the jump to humans we need to protect wild animals and their habitats. to know to diseases to sulk from intensive livestock farming the earth the grid animals are more susceptible to disease and so they're given blanket antibiotics this can. resistant bacteria which can be transmitted to people. intensive farming also causes of the problems it stresses genetic diversity by repressing the farm animals. meat turtle your pigs. styria and chickens and the ancient british white.

people have been breeding in domesticated animals for at least 11000 years. nowadays 180 breeds of farm animals are endangered in europe alone among them the german saddle back. at the head open air museum folk in favor is working to preserve the rare breed with its distinctive features for one thing its meat tastes very different from that of pigs raised on a factory farm. we have. in the autumn when the acorns fall to the ground in the saddle back seat lots and lots of them are so their meat has this wonderful acorn and flavor it's something you don't often find nowadays we also make sausage out of the meat and it's very special those. pigs have been bred mainly for their meat. the german saddleback has a generous layer of fat which nearly smelled it's due.

tastes changed in the 1960 s. and demand for fatty meat declined. the food industry responded by getting it scientists to breed futuristic new pigs with more meat chops all the same size and crucially a lot less fat. the breeders did not care much about the health or well being of the animals these newfangled swine were too big and heavy for their legs and hearts specimens were put on treadmills so the strongest could be identified. and allowed to have offspring. these pigs were longer and had 2 more ribs than most and lots of lean flesh. but modern pigs are susceptible to stress for example when being transported to slaughter but efforts are underway to breed a variety that takes even that in its stride. old breeds are more robust and on the whole healthier and that probably has to do with their genetic make up.

there are collections of genetic material from old breeds of farm animals. they are very important for research and for breeding purposes. one aim is to combine genes from different breeds in order to reduce the susceptibility to certain diseases. but it's far from certain that epidemics of say swine fever could be prevented this way. german red mountain cattle are long lived and undemanding. make have without complaining or complications for the most part. in the olden days there were no vets just down the road so everything had to just function properly and that's the case here even though it's cold when they have their tops in fabry humans rarely have to get involved that's a great advantage to very healthy. wouldn't be ancient celts are believed to have bred these red brown cattle 2000 or more years ago the cattle provide milk and meat

and can be harnessed to plough the fields this breed is endangered outgunned by modern turbo cows. breeders have been adapting cows to the requirements of industrial farming. new greens have been designed on the drawing board. the cow's udder was bred to fit the shape of a milking machine milk production increased the body's use of feed was optimized. red mountain cattle were regarded as extinct. in the 1970 s. but thanks to a coincidence it has survived a stud seen it was discovered at a breeding facility. as he was known sire to a new generation and in doing so saved the breed from extinction the cattle's characteristics could be useful in the future. and your these men even if they're no longer used in production their genetic material is needed for further breeding

and we can't know today exactly what kind of breeding requirements will have a century from now. as in. the change of scene their own mountains of central germany are home to the ruined sheep its positive characteristics were also nearly forgotten. once demand for its ruined sheep pelts dried up its numbers dropped from hundreds of thousands to just a few 100 creatures the sheep scratchy wool became unmarketable. modern sheep were needed to provide more meat more milk and above all softer wool. none of this applies to the ruined sheep but still it's being rediscovered for landscaping purposes modern sheep brains often suffer from book disorders but not the ruined their trousers are especially tough. thanks to this hardness they have no problem grazing year round and since sheep are picky eaters they help maintain sensitive ecosystems. this is silver thistle an emblem of the run their only chance

of survival depends on the grazing strategy used and the sheep are best suited to the purpose of the sheep choose what they like and they leave the rest alone that means this biodiversity already exists i mean actually want more of this down dismissed you know. old farm animals they are still useful for landscape maintenance for their ease of care for their taste and for their genetic diversity . yeah. if outlet is right why are great but i'm a bit of a dilemma to you the science question you'd like us to answer send it in if we featured on the show you get in little surprise as a thank you. but come on just ask. one of here most stories about science then visit our website and check us out on

twitter. the boy. that's all from us i tomorrow today thanks for joining us. we're back next week talk then stay healthy and curious.

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you can also find us at pretty value dot com look for it slash science. every 2 seconds a person is forced to flee their home nearly 71000000 people have been forcibly displaced. the consequences have been disastrous for our documentary series displaced depicts dramatic humanitarian crises around the world you know. forget them when i didn't go to university to kill people that day so i don't want to. had my boss come to me and tell me to kill someone and if i don't they'll kill me and. keep these things for their lives and their future so they seek refuge abroad. scares me the most about this state he seems to rise is that someday we won't even see the relief. but what will become of those who stay behind and simply

my husband went to peru because of the crisis. if he hadn't gone there we would have died of hunger. rather sentimental down. just starts october 16th g.w. . this is news and these are our top stories u.s. president donald trump has briefly left hospital in a motorcade to wipe to supporters gathered outside before returning earlier his medical team said he was improving and suggested he could be discharged as early as monday trumps dr berfield the president is on a course of steroids and is experiencing ups and downs particularly when. police in bellerose have used water cannon to break up a rally.