courageous women are calling for democracy, freedom, and basic rights.

in northern canada, we meet people being forced out of their homes by accelerating climate change. but first we head to syria, where one influential tribe wants to help shape the future of the war-ravaged country. in syria, the war is not yet over. in the northwest, forces loyal to president bashar al-assad have mount an attackn the country'last majorpposition stronghold. over the years, regionalribes ha also takeup arms, mnly against islamistate milints. sometimes at the side ofssad, other tis at the se of his opponents. the ammar is aribal confederation based in northeast syria and iraq. it is one of the largest clans of the region. its syrian headquarters are in tell alo and its leader says tribes like his should play a key role in peace negotiations for the future of their country. reporter: when the weather

allows, sheikh humaydi daham al-hadi gathers his closest allies in a makeshift tent. he often serves them mutton for lunch. it's an old tradition, and one that the head of the shammar tribe keeps alive. it's rooted in the times when the shammar lived a nomadic life crisscrossing the arab world. until recently, the shammar fought bitterly against the islamic state's fiters. as a rest, weaponsre still commonplace here, even if nowadays they're only used for sport. the shammar e among th reon's most werful tris, with mlions of mbers. d althoughhe war in ria is not over yet, a measure of calm now prevails in the northeast. sheikh humaydi hopes he can help shape post-war politics.

sheikh humaydi: if you want to solve problems, the tribes are important. 90% of people here belong to a tribe, whether they're arab, kurdish, or christian. we all share the same culture, because these local tribes all have the same traditions and customs. reporter: humaydi's palace is in tell alo, a small village in northern syria. this is where the shammar leader meets petitioners, allies, and other sheikhs. together with his advisors, he decides on issues affecting the shammar's future. he also mediates in disputes between members of the tribe, and distributes aid to the needy. tell alo is a long way from damascus. that's always afforded the shammar a certain autonomy in their decision-making. the tribal leaders even act as a substitute for central government. the sheikh's revenues come from the region's oil fields and tolls levied on travelers.

they pay for his militia and support for tribal members. humaydi's fighters halted the advance of the self-proclaimed islamic state, just short of tell alo. a hastily erected wall of earth near the village is a reminder of how close the front line came. it was used for cover, and as a barrier against lamic stat trucks packed with explosives. the militia is led by humaydi's son bandar. they call thselves the al-sanadid forces, or forces of the brave. for a long time th fought alongse the kurdagainst their common enemy. i.s. wanted absolute power over the gion. e fightingas fierce and took a heavy toll. bandar: they surrounded us. onof our figers sacrificed his own life to save us. porter: hiarabian hoes are ndar's pri and joy, d also tradition. they used to carry warriors into battle. today, the tribe's militia use

assault weapons and four-by-fours. the shammar might have fought off the islamic state, but peace is fragile. the so-called caliphate casts a long shadow. bandar: it had been obvious for some time at the i.s. would face military defeat. but it's the i.s. ideology that worries me it's taken rt in children's heads, and won't be so easy to shake off. reporter: roads and tracks here are still secured by checkpoints, where the al-sanadid control vehicles. women are rarely seen on the streets. this is a man's world, and women are restricted to working in the fields and t household. the next morning in the palace begins with praise for sheikh humaydi.

although figing contins in so parts of ria, the shammar chief is looking to the future. during the war, humaydi's militia called the shots in the northeast. syrian president bashar al-assad's troops had been quick to make themselves scarce. that could easily change now, and sheikh humaydi is looking to cut a deal with damascus. in march he went to talks with the assad government. sheikh humaydi: we're not negotiating yet. the meetings were aimed at bringing about peace, and putting an end to the hatred between ethnic groups, religions, and political parties. it's our task to diffuse the hatred others stirred up. reporter: he advises parties who want to maintain autonomy achieved in the war to seek coromise witthe governnt. sheikh humaydi: the first thing we must do is put an end to the

destruction and bloodshed. fe is moremportant tn death, our souls more important than those of the dead. reporter: the shammar have survived the war. and sheikh humaydi is hoping for a permanent peace. host: overhe past mohs, pele in sudas capital khartoum have been taking to the streets, demanding basic rights and a shifto democra. april, thprotests hped trigger the fall of president omar al-bashir. a military coup put an end to his 30-year dictatorship. now, many sudanese want the generals who toppled bashir to also surrender power. in their place they want a civilian government, and free elections. and there are signs of hope. over the next few years, a broadly civilian government is tasked with transitioning the

country towards democracy. and many women want to play a role in this too. porter: rifka leads the chants the 18-year-old student is part of sudan's revolutionary movement, one that features women heading the calls for change. rifka: my aim is to become a politician or a minister in a new government. women need to have a voice. reporter: rifka, walaa, ola, and thousands of other women were instrumental in the developments that led to the ousting of dictator omar al-bashir. they were actively involved in the revolution from the outset with their banners and chants, first driving the protests, and eventually leading them too. women have often outnumbered men at the demonstrations, in the process getting first-hand

experience of the regime's brutal rule and the hatred of religious zealots. walaa: it's our right to have some area to talk, to show the world that we can do things. raida: this isn't a revolution against islam. they exploit islam for their own purposes. we are not against islam. we are against people who distort islam's message to their own advantage. ola: i was arrested at a demonstration in khartoum. they took us away in police vans. i saw them beating the men, and torturing women who had been found with banners. they let me go because i didn't have one. reporter: those traumatic experiences were far from the exception. rifka herself has been arrested

five times, and has been subjected to beatings and torture with electric shocks. but her ordeal served only to strengthen her resolve. she began picking up tear-gas grenades launched by the police and throwing them back, to protect others around her. this video, posted online, made her famous. rifka: i was at the front. some protesters died right next to me, but i wasn't afraid. throwing back the teargas grenades came naturally, even if i knew i could lose a hand or be blinded, and breathing was extremely painful. reporter: khartoum remains in a state of flux. first, the protesters instigated the removal of infamous dictator al-bashir from his palace. but now, they want to see the army generals who finally toppled him step down too.

they're calling for freedom, peace, and equal opportunities for women. that is itself a revolution in a country where women have traditionally been denied a voice. nahid gabralla is a veteran in the field. she's been fighting for women's rights in jobs and education since the 1980's. nahid: women from the start, we are the victims of the al-bashir regime. in all areas of sudan. public order law, family law, all laws relating to women's rights. all policies, suppression for women. they were directly affected by the economic crisis. reporter: now, finally, it really is her country too. rifka wears the colors of the nation's flag with pride, although the struggle is not over. rifka: equal rights for women really would be a dream. for now there's no equality, but

there are many things that bring us together. as sudanese, we all have the same rights. reporter: peace and freedom for men and women -- a cause she and her fellow protestors will continue taking to the streets for with newfound confidence. host: for decades, nasa's satellites have been tracking changes to the ice in the arctic. and their findings are deeply alarming. the arctic icecap is melting, and at a concerning rate. over recent decades, the amount of older, thicker ice in particular has been shrinking. the area of open sea is expanding and freezing-over later in the year, with devastating consequences for people and animals. residents of the canadian town of tuktoyaktuk on the arctic coast know that only too well. the ground is literally falling

away beneath their feet. reporter: it's half past 9:00 in the morning before the sun finally appears on the horizon, here deep inside the arctic circle. we're on our way from the town of inuvik to tuktoyaktuk, one of the northernmost communities on the canadian mainland. this road was only built 1.5 years ago. it links the small town on the shores of the arctic ocean with the economic centers in the south. it's nearly 3500 kilometers from here to edmonton, the nearest major city. conditions are harsh for this remote community. and despite the new road, they're now getting even tougher. local resident sandy adam says the lives of the locals have changed dramatically in recent years. there used to be three rows of houses standing here in front of his house. but they've all been washed

away. this summer, his own house will likely meet the same fate, when the winter ice melts and the frozen arctic ocean becomes a raging sea. sandy: my house, probably going to rot my foundations. you know, they're only wood. a little bit of water in it and it'll get rotten. reporter: it's a problem that's affecting everyone here on the shores of the arctic ocean. sandy adam says the temperatures are rising, the winters are starting later, and the summers earlier. the family now need to move from the house they've always lived in. sarah: i have no choice. i'm thinking about my children, my grandchildren, so we have to move my house. it's going to be hard to get used to, but we have to. we're going to get all in the water soon. reporter: but it's not just the erosion that's threatening their future. going out to the edge of the town, we're given a unique

insight into a fascinating world, six meters below ground. sandy adam's son jeffrey takes us to the local ice house. for dedes, meahas been stored here in these rooms in the permafrost. jeffre it was all made by picks and shovels. it's all ice. reporter: for thousands of years, solid ice has formed the foundation on which everything here stands. to remain stable, permafrost requires an average year-round temperature of below minus one degree celsius. if the average temperature rises beyond that, the ice melts. that would transform vast swathes of land here in northern canada into a huge swamp, with repercussions for the entire planet. we take a flight over the

region, joining a research team from the german aerospace center. the scientists are directing radar beams at the earth, using four different frequencies that penetrate to various depths. ralf horn and his colleagues are conducting experiments to see how the permafrost on our planet is changing. the canadian arctic is the perfect environment for their work. ralf: this floating landscape has all the different facets of permafrost. this is exactly the place we want to be with this equipment. reporter: the test setup is a global first and is designed to give us a better understanding of the changes taking place in permafrost regions. a huge risk for humanity lies dormant in these areas. that's because permafrost soils hold more than twice as much carbon as the earth's atmosphere

does. so it's only the ice that is preventing vast amounts of greenhouse gases being released into the air. a short while later, back down on the ground in the wilderness of ice and snow, the scientists dig up a radar reflector that provided a reference point for the measurements taken from the plane. there's a bitter wind blowing. working in an arctic storm is not something the german scientists do every day. ralf: it certainly makes a change from the office. it keeps us on our toes. if i had to do this all the time it would be tough. but as it is, it's fine. at least i'll sleep well tonight. reporter: they take samples of the snow as a reference guide for their radar measurements. they want to know exactly what's happening. after all, there's a lot at stake.

irena: you have a lot of organic material stored here in the ground, so if the permafrost thaws, vast amounts of gases would be released into the atmosphere. we're talking about mainly methane and co2, which would speed up the process of climate change even more. reporter: around 50 kilometers further west, canadian scientists are also taking samples. they're measuring the thickness of the ice on the frozen mckenzie river. a local hunter and trapper has come out with them to provide protection should any wild animals pose a threat. life here has changed in recent years. miles: a lot of us are confused. animals are confused. the grizzly bears are waking up and getting out of their dens. it's only the 19th of march, and that's a month early. now it's warming up we have all these other insects coming up we never saw before.

before reporter: the ice is just 60 centimeters thick. miles says that's nowhere near enough for this time of year. miles: since i was a kid the ice was thker, seveno eight feet. my dad used to put me down with my ankles, going down a shaving hole, i used to fill up a pail and he would pull it up with a string, toss it, and he chiseled some more and i'd go down, he holds me down and i fill up the pail like this, and then he pulls it out. it must have been eight feet before we hit water back then. reporter: eight feet, or nearly 2.5 meters, compared with just 60 centimeters today. that's a huge change that's occurred in just a few decades. one thing is clear -- disaster is looming, and the process has long been underway. even though the dazzling beauty of the canadian arctic could easily lull you into a false

sense of security. host: now we head from canada to siberia in russia, home to lake baikal. the vast basin is 600 kilometers long and up to 80 kilometers wide. at around 25 million years old, it's also considered the world's oldest lake. and it's the deepest, 1642 meters deep, in fact. it contains a fifth of our planet's fresh surface water, more than 23,000 cubic kilometers worth. it also has a unique eco-system of around 2600 animal and plant species, including the world's only freshwater seals. and it's unusually clear -- one reason why it's under threat. reporterlake baikais waking up from its winter slumber.

the ice is slowly receding, and revealing a blot on the landscape. the lake's sensitive wetlands have bn cut throh by gigantic peline ditcs. they're part of construction work for a new water bottling plant that will source drinking water in lake baikal. 80% will go to export, mainly to china. biologist vitaly ryabtsev plains wt's planne vitalywater isumped thugh the pis. the ideaehind thfactory to takwater fr the deps of e lake. but get the, they he to traver 2.5 kileters of shallows. reporter: those are the areas which worry the biologist. for years he's been seeing the number of birds here on the southern shore decline.

this algae also tells him that the lake's in bad shape. vitaly: lake baikal contains 20% of the world's freshwater. there's nowhere else like it. lake baikal is the planet's well, and that's how we've got to treat it. the shores have to be kept clean, no rubbish, and they shouldn't be built up. otherwise we'll lose this natural wonder. reporter: rjabzev and the people of kultuk have been battling against the water plant for months. it belongs to a chinese businessman. a million people signed a petition against it. they've managed to get construction suspended, at least for now. but a final decision has yet to be made. vitaly: the fact that the plant belongs to a chinese company sparked massive protests, in particular among those who signed the petition. there's never been so many

signatures collected here. it's siberians protesting against the chinese expansion that's currently underway. reporter: rjabzev meets activist stanislav fillipov. he collect the signares and now heants publiprosecutor to invesgate the pnned faory. stanislav: we've not lost hope. we want the wetlands declared a protectearea. reporter: lake baikal doesn't only attract chinese businesspeople. every year over a million tourists come here, in summer and in winter. and most of these foreign visitors come from china. >> a friend of mine had been here before. and he told me that is is a place ke paradis

>> there's a famous song in inese, in ina. we hrd this song wn we were children. wenow baikal lake by this song. ♪ porter: livyanka is ke ikal's main tourist destination. in the summer season, thousands of chinese comhere everyay. and a growg number ohotels are chinese-owned. one is being built right outside a guest house owned by andrei sukhanov. construction has been temporarily halted after the protests. but suchanov still has to climb his steps for a view of the lake. andrei: i moved to lake baikal especially so i could enjoy the view of the lake every morning. now they've blocked my entire view. reporter: these days, his guesthouse is usually empty in winter. he says there's too much competition from the new hotels.

but they weren't here before, and now they are. if we want to have them here, then we should build a village just for them somewhere else on lake baikal, because there are so many of them. reporter: locals in lake baikal feel overwhelmed. and they claim the chinese don't behave the way visitors should. the planned bottling factory is stoking the anti-chinese sentiment in kultuk. bustanislav lippov andhe othe feel ju as much betrayed by their politians, antheir falspromises. stanislav: people here don't believe there'lle new jobs. the chinese will bring their own people. reporter: filippov says ongood thg has emerd -- the bottling pnt disputeas shown kultuk's citizens that they can

achieve a lot when they ick together. lake baikal, a vital freshwater reserve and a tourist hotspot. but business poses a growing threat to wildlife and local we're back next week. in the meantime, please send us your thoughts and comments. drop us a line to global3000@dw.com. and you'll find us on facebook, dw women. bye for now. ♪ [captioning performed by the national captioning institute, which is responsible for its caption content and accuracy. visit ncicap.org]

narrator: on this episode of "earth focus," the illegal lumber trade is a multi-million-dollar business spanning the globe. in the northwest united states, scientists are using innovative methods to stop lumber from entering the country, while in brazil, violent clashes have erupted at the source, where indigenous groups are trying to stop poachers from decimating their forest.