ah ah, life on earth could not exist without this wonderful chemical compound. h 2 o. in a never ending cycle, water circulates the planet preserving the lives of its inhabitants over millennia . but climate change is throwing this dependable system out of balance. add to that arising demand for water caused by industry agriculture and the world's growing population. and we run the risk of running out of this precious resource. but new technologies looking to nature as a role model. and pre historic knowledge gleaned from i gone cultures are helping researchers worldwide come up with new ideas to sustainably protect our drinking water. and this german research vessel heads out to sea to explore fresh water reserves of great magnitude. ah, every spring glacier ologist danielle fatty naughty and his team make their way up to the alleged glacier and switzerland below the young, foul yoke research station at an elevation of 3350 meters. they measure the depth of the snow. the glaciers of the alps play a vital role in supplying water to millions of people. they feed water into central, europe's largest river systems, the danube, the rhine, the po, and the rhone. it's who sent the glitches either nist's. unfortunately, the glaciers condition is none too pleasing, as right before the sun's place. he is currently lose some 2 percent of their massey cheer food beyond that. so in the last 5 years, but they've lost 10 percent of their entire mile isn't for denise. and sadly, the prognosis for the next 100 years is not terribly rosy, either on the lease rosa, if we don't manage to lower greenhouse gas emission. so this was if the way things are going continue as you write that, then we'll likely see only the last remnants of ice head where we are currently stand. there must be no more than that incredible mission now. ah, for more than a century, scientists have been coming to this area to assess the health of the alleged glacier. how has the snow cover changed over this period of time? with the results of these measurements, the researchers can track the changes to the glaciers mass and determine exactly how much of its volume is lost each year. subsequent forecasts include global climate data at the university of oxford, fredericka or toll works with the environmental change institute. her research focuses on extreme weather events related to climate change. daughters does the atmosphere of that because the atmosphere is getting warmer during the more water is evaporating. size, which means young water vapor is entering the atmosphere elephant. and then coming out again, it's re read out so the whole balance between evaporation, a dual and precipitation, which existed with relatively stable global temperatures as the century law. temper is becoming unstable and being thrown off kilter, our season, stubborn gleiss, kathy's cooper. and that poses a great threat to the drinking water supply of all living beings because the amount of fresh water on earth is limited. ah, that's because almost all the water on our planet is held in the oceans. so it's salt water, some 96.5 percent the amount of fresh water is therefore relatively small. just 3.5 percent. and most of that is stored as ice or snow in mountainous regions and at the poles. mm. that leaves only a fraction. just a 0.3 percent of the water on earth is accessible to humans as drinking water. currently 22 kilometers in length. the alleged glacier is the biggest glacier in the alps. it's vast size means short term weather events are barely noticeable. that makes the glacier a reliable climate indicator suitable for long term observation. during their last measurements in 2020, the glacier ologist is found. the amount of snow had reached a record low, the lowest amount since the 1st measurement was taken in 1918 readers from sunni. it is the sphere in physics. i will how this works is we're basically on location twice year into this winter come once of the end of winter will remain. so right now we're trying to measure the amounts of snowfall over the winter. dr. ball. as you can see, we use this tool to drill down to last. he has level his through and that tells us how much precipitation there has been the cycle. and then we come again in the fall and take a reading from the poll. the sticking out al, snow, how much is the snow settled out of me? how much snow has been added or how much has melted away it's overshoot. is that sort of defeat? read up kesh mode since the team has evaluated various scenarios. if global warming continues that the current rate, the scientists expect the alpine glaciers will have melted away entirely by the year 2140 per cent, could survive if the temperature increase were limited to a maximum of 1.7 degrees celsius. of course, this would have major consequences for the water supply. in the short term, the melting ice would mean more water would be available. but in the long run, the water from the glaciers would be sorely missed. in more instinct, the defect in living in the golden age of our water supply boat. but in the long term, is that when the glaciers recede and get smaller, but they won't be able to supply as much water leaf will come. when these water reservoirs disappear than comcast, there will be even less water. the 2nd effect, the glaciers after has when the happens over the course of years effect, they serve a storage function on the call sized in windsor. despite place his collect snow into which simply lies there and is only released in the summer beaten. vist. yes, that means when the glaciers are no longer there, so in the summer time will be missing the water that's currently produced by their melting lhasa was the moment that so basically in future summers, there will only be water when it rains to crimp to kazama north and west of in a signal given the increasing frequency of droughts and central and especially southern europe, having to rely mainly on rain each summer could be extremely problematic. one countermeasure could be to collect the melted glacier water and man made reservoirs, thereby artificially replicating the glaciers storage function was sir vista, gets in his presence, i'd mouth for me. an important part of this discussions is this technocratic approach. the people want to tackle the problem with technology. hey, give it that. when it comes to landscapes like this, i got it. i think we need to ask ourselves the question. it didn't was really doesn't nature have a value in and of itself. so jim is alpha and can we just leave it the way it is? how much? because it's beautiful. and do we really have to build something else in these areas? um, and these are questions the science can provide yes or no answers to the business of anna and thought, rather, it's a decision that society needs to maya i. so we should at least consider exactly what it is we want to do. of that it's a window, the road lack of investment in albertville. the analysis of the measurement data shows last winter, this area received more snowfall than in any winter in the last 20 years. that's good news, but not a turning point. the melt water from the latch and roan glaciers converge and the mighty rhone river. what happens when streams which are fed by small snowfields dry, can already be seen in several mountain regions of switzerland. in hot summers emergency water supplies must be delivered by helicopter agriculture industry and some 10000000 people rely on the water from the rhone mon toll lozano and geneva all border on lake geneva, one of the largest fresh water reserves in western europe. but for how much longer, not only are the glaciers shrinking their precious melt, water is flowing more or less straight into the sea. since the rhone was transformed into a veritable water super highway for industry and transport, gone or the flood plains, which would allow water to sleep in and fill up aquifers along the river or capture flood waters caused by heavy rainfall. one exception can be found near the medieval town of avignon at the e deal about the last one of the largest river islands in europe. it's flood plain forests not only serves as a refuge for animals and plants, but also takes in flood waters to allowing the rhone to spread well beyond its banks. it's an effective means of flood protection just outside the gates of avignon. a river that has room to spread out offers yet another decisive advantage says she'd blow who's been fighting for 20 years to restore this river scape to its natural state a feel from you or them. so you feel can be that. what if we give a river like the rhone, enough space, you and don't take measures to combat letting you know this, the ground water will replenish and clean itself, but you still wish. but if we have a catalyzed closed in river, gonna the water rushes through to the sea and can't steep into the ground the door shall hidden up. if we create a few open spaces for rivers where they can overflow their banks a bit, when there's flooding, the aquifers are refilled, automatically leave yet it's been tastic and free of charge if they would, but of boosted all. but it's difficult to reactivate these natural cycles, as there are competing interests to consider in the comma region, locks irrigation canals for rise fields and its famous salt water lagoons. the it don't have forced to the river into man made channels and disrupted the river. delta's natural course as to where he is like the romans play a special role in the water cycle. they are where fresh water and salt water, meat striking a delicate balance. flo state us out of some awesome flu season. i'm hot rhythm, deltas c, especially those of large rivers are a hot salt of climate changing to the effect of rising sea levels are especially noticeable. and that is just a matter of spiegel and style car example done. then when there's a storm surge, the salt water from the sea will come significantly further in land ice when the sea level is high than it would if the sea level will lower. and i'm needing it on meals, feet, it deaf, higher vila. and since it's been channel lies, the rhone no longer flushes enough sediment into the delta, leaving little to stop surges from the rising sea models created by the european space agency from satellite data, showed that the camera could be completely under water in a 100 years. even now the intruding salt water poses a danger, not only to coastal ecosystems, but to residential areas as well. that so gung, so think vasa, aunt on this already to day access to drinking water and a safe, reliable drinking water supply is a defining feature of whether an area can be economically successful here. look like him sooner. zine can in the german state of lower san sunny, 86 percent of the states drinking water comes from ground water. that's above the german average. lower sacks and he has 750 kilometers of coastline on the north sea . the rising sea water can be held back with dikes above ground. but what does the situation look like? deep underground? yeah, under crystal on the coast, we clearly have sea water salen, zation, or salt water intrusions is that's the case and lower saxony and in many other coastal areas. the deeper down you go, the higher the salinity in the ground water, the team from the state office for mining energy and geology and hanover, is trying to find out where salt water is located in the ground. to the way to produce more precisely, it's about finding the boundary between salt water and fresh water under ground. to detect this, the team works with high tech equipment. the main component is a huge antenna, a wire frame, 20 meters in diameter, which can both send and receive electromagnetic waves. ah, the technology was developed at o, who's university in denmark, and has been in use world wide since 2005. from the deserts of australia to the ice of the arctic. a helicopter flies, the measuring antenna about 30 meters above the surface of the terrain. electro magnetic fields deliver information from depths down to 300 meters as a mom to compensate an upper deck he sickly, but you get an image of the distribution of specific electrical conductivity under ground. for example, since clay has a very high electrical conductivity, it's a good conductor, keys, a gravel and sand have significantly lower conductivity, and from so there's the information on the composition of the aquifer, the sub soil and on the dissolved salts in the ground water, which also affect conductivity lights. hm. that means the more dissolved salt. gimme the more sailing the ground water is. the more conductive it is. so the switch dec i, they just us. the end result is a detailed picture of the salt content and ground water. the blue areas near the coast indicate there is salt water, just a few meters below the surface. and the green area there is fresh water at a depth of 100 meters. this is where drinking water can be extracted. just like in the red colored areas where fresh water can be found in layers that extend even further underground. the data also offer some unexpected insights from soups that we've found floating layers of salt water, that's basically a subject unto itself. to move on top, you've got salt water, then comes a binding layer of clay where the salt water is floated up. hm isn't then below the clay, there's fresh water on the missouri. something completely unknown before, at least because those salt water layers are probably the remnants of long ago floods. ones that occurred before people pushed the sea back with dikes. finding the exact locations of fresh water and salt water. and the sub soil is fundamental for local water suppliers. but salt water deposits warranty only unexpected discovery. here. i say it was hostile area is quite interesting. you can easily recognise fresh water outlets under the mud plastic, you know, at low tide, fresh water flows out is really far into the mud flaps even with these and, and we could actually show that with this data onto the so these are the interesting highlights. we've stumbled upon to highlights of the one and 2 finding previously unknown deposits of fresh water is also the goal of this research expedition. in the summer of 2020 the german research vessel zona, the german word for sun set sail for the mediterranean. besides the crew, there were 28 scientists on board along with tons of equipment to study the sea bed . and what lies beneath it. the ship is bound for malta. off the coast of the island country and the mediterranean researchers from the g o mar, center, and keel and their multi colleagues plan to use their technology to collect as much data as possible. they're investigating a global phenomenon which could help coastal regions that suffer from a lack of fresh water. so an, an antique, a m was to live in, in ancient times. people knew they had to be grandma to somewhere in this bed because they knew that what fresh water spring time and some of these springs were so powerful that the water came right up to the surface and admitted in the mediterranean, french, more in arabia the ships could supply themselves with jeff, from nice pockets of fresh water on the sea, safe and health welfare should gal exams, and humble. it's did the same thing of cuba. for example, while cuba mother union is a scientist, g omar, the helmets center for ocean research and keel. the geophysicist heads a team that specializes in electromagnetic measuring techniques. in contrast to the helicopter antenna used in lower saxony, the main component here is a device for underwater use nicknamed the pig because one of its 4 runners was originally painted pink. it's highly complex electronics were developed and built here at the institute. the pig sends electromagnetic waves deep under ground, the signals change according to the conductivity of the ground. these changes can be measured and used to infer the existence of possible fresh water deposits and the sea bed. by the end of the expedition, the robust device will have covered 50 kilometers of the ocean floor in total however, collecting electromagnetic measurements with the pig is just one part of the scientists work. they conduct a variety of technically demanding experiments on board by taking water samples at various depths, for example, they can determine the salinity of the water. the experiments go on around the clock with the team's working and shifts. seismic devices provide an overview of the sea by the geological structure. acoustic signals are sent downwards and their eco, let's the researchers draw conclusions about the composition of the sediment and rock their sediment corps health to complete the picture, as well as to verify and adjust earlier models with there's a lot of hope riding on these sediment corps since they could provide direct proof of fresh water sources. malta c bad proves difficult to work with since the seafloor is extremely hard. just 14 samples of sediment core make it safely on board. the corps are then carefully prepared. only when they're back in keel will the team be able to test the sediment for possible traces of fresh water then comes the most delicate part of the mission. the pig is prepared for the electromagnetic measurement. the entire apparatus consisting of a transmitter and receiver hangs on a cable that's almost a kilometer long. this will commish noah not to listen. i know we know i'm looking for a groundwater in just one place than guns. we want to scan the entire seed batch, the ground water to pose a maximum to find on what we do is follow various profiles. and then we bring the entire device that is this the receiver and then towards the end the tag, which is quite heavy, down to the c bad. and then the whole, it's along the sea floor. food is we can get 2 kilometers a profile to her, our pushed under go font the relevance of this research is clear, given the huge amount of offshore fresh water thought to exist around the globe. it's total volume is estimated at 1000000 cubic kilometers. twice the amount of water and the black sea. the impetus for this expedition came from researchers at the university of malta, who laid the groundwork for the international collaboration. the small island nation located south of sicily is extremely dry, and one of the most densely populated regions in the world. it's area of 316 square kilometers, accommodates about 500000 residents and some $2000000.00 tourists each year. like many coastal countries, including israel and the gulf states or the us state of california, malta cannot meet its fresh water needs from aquifers alone. these saturated rock layers don't release enough ground water to supply the demand from tourism industry and agriculture and low. so we don't have any natural resources like lakes and rivers, so we have to divert to the underground metro water on the see around us. not sure . water is restricted to the size of the island. so we had to go as we're and we chose reverse osmosis about 40 years ago, m as a technology. and it's worked. and our plants are still running very efficiently. we have evolved and improved technology and i will have reproducing 60 percent of the water acquired by the monkeys population from our 3 versus most plans reverse osmosis functions, according to a simple, yet ingenious mechanical principle. sea water is forced through a special membrane under great pressure, filtering out salt and other minerals and the process these minerals must be re introduced afterwards to make the water fit for human consumption. close to 15000 desalination plants are in use world wide. people count on this technology and coastal areas where drinking water is scarce. but river saws moses consumes a lot of energy and it leaves behind a concentrated and partly contaminated brine. that's usually just channeled back into the sea. although researchers are looking for better ways to dispose of it, mal