so, in a bid to get to government targets of bringing down pollution levels, highways england are introducing four stretches of motorway in england which will have a permanent 60 mph speed limit. one of those stretches is behind me here on the m1 in south yorkshire between sheffield and rotherham. there is another one in northern england over the pennines — the m602 that comes into manchester for the west and liverpool. and two stretches of motorway on the m5 and the m6, just stretches about four miles long or less, around birmingham where those speed restrictions will come into place. the difference is, we are all used to temporary speed limits on motorways at times. but this will be a permanent one. some time between now and the beginning of october, those speed limits will be introduced. they will be in force 21w, so even if the road is quiet, you won't be able to drive at 70 mph. there is an awareness campaign that will need to be done as well, and this is part of it,

to actually say to people, please don't think that the default speed limit, which is a 70 on the motorway, will be in place if those roads are quiet. those stretches of motorway will have a permanent 60mph speed limit. if you break that limit, you run the risk of a fine and penalty points. so, this will take place for a year, potentially, 12 months, until they review it to see whether they might roll it out further. but this is part of bringing down pollution levels, but ultimately, highways england are saying in the long run it is down to what comes out of your exhaust or tailpipe on your car. most of us drive petrol or diesel cars at the moment. the aspiration is to get more of us driving electric cars, hybrids in the future, which will have a dramatic effect on the levels of pollution. but for the time being, this is a scheme to try and reduce pollution levels and they say by lowering the speed limit, there will be less pollution through those areas and better air quality. now on bbc news, deforestation has

skyrocketed in colombia since the peace deal of 2016. our world joins a team of scientists from the royal botanic gardens. in the forests of colombia, nature is under attack. since the civil war ended in 2016, deforestation has skyrocketed. i'm frank gardnerand i am heading into what remains of the virgin tropical rainforest. i traded in my wheelchair for a packhorse and am tested to my limits. i think this is too dangerous. i don't think i can do this. i am joining a crack team of scientists from the royal botanic gardens, kew. they are on a mission to discover and save unique plant species before they vanish forever.

i am going to bear witness on the frontline of rainforest conservation. this is where the journey begins — not in colombia, but in the royal botanic gardens, kew, london. kew is the world leader in developing plant science. the botanists are preparing for their mission to discover new species. and it is from here that this expedition will be launched. i have come here to see the expedition leader, doctor mauricio de bernardos. he works in a library

for lab specimens. this is where we identify new plants. we believe we have more than 200,000 different species here. you are a botanist and a biologist. and a scientist and an explorer in some sense. what are you expecting to get from this mission? the most remote areas are the best preserved and this is going to be our most important expedition. we're going to try to get into the heart of this area. we do not know what we expect to find. what is at stake with this whole trip that we're doing? why is this so important? we are in a race against time to protect this biodiversity from disappearing. we have rapid deforestation. we see how we are losing this forest

very quickly and ourjob is to get an understanding about the diversity of these resources as well as their importance. in 2016, the colombian government signed a peace deal with the farc rebels. for more than half a century, civil war actually slowed the pace of deforestation. but now remote tracts of land have opened up. farmers, loggers, and miners are scrambling for resources. colombia is now reportedly losing 3,000 square kilometres of forest every year. we are travelling to an area famous for its emerald mines, western boyaca. this is a bittersweet

journey for me. this could be the last time that i could see this forest. if i come back in ten years, this forest could be gone. colombia is still an eden. it's the second most biodiverse country in the world, after brazil. i may be the bbc‘s security correspondent, but my passion is for nature. you know, just look around you. there's incredible scenery. it is such a privilege to be here. i love being surrounded by the sounds and smells of nature. nature has always been something of an antidote to myjob as a security correspondent. in 2004, i was shot and partly paralysed while on the job. i won't deny, i have a certain trepidation about the trip itself because everybody else is walking.

i will need to do this on horseback or i will not make it. the team assemble at the edge of the rainforest in las quinchas. it's going to be a beautiful day. yes, it is going to be a beautiful day. this is the first time this area will be explored by scientists. for so many years, conflict and criminality made this area inaccessible to outsiders. if you see a snake, everybody please freeze, don't move. we are going to carry radios at all times. you, actually, frank, you'll have a radio. so this is going to be your radio. i'm going to be quite busy trying to control the horse. well, yes, maybe we can put this

on the horse so you can have something that you can... the horse can do the radio. there is a bit of a risk here. my legs are like honeycomb, the bones. i cannot afford to fall off and break things. at the beginning of the track is a steep descent. the botanists hope to find new species deep inside the forest. but i am unable to hold on with my legs. guys, i don't think i can do this. i'm going to fall off. i think this is just too dangerous. i mean, it breaks my heart, ijust... i think you will have to carry on without me. but the local guides come up with an idea.

well done. 0k. i am so thrilled that despite my injuries, thanks to the endurance and kindness of these guys, i am able to see this amazing scenery. primary forests are the most bio—diverse terrestrial ecosystems anywhere on the planet. forests are not only vital in mitigating climate change, the botanists hope to find plants with untold potential.

they get to work collecting specimens. we don't know what it is. it could be a philodendron. beautiful. one of the local guides believes that he has chanced on something extraordinary. this, we actually don't know exactly what it is. it could be something new. we are the first botanists collecting in this area. so basically every single collection is a new report

for science in this area. the scientists will take the cuttings to the laboratory for further examination, in kew. beyond the fact that it is scientifically interesting, what does it mean to find new species like this in a remote forest? in a country like this, hugely biodiverse, we still do not know how many species are out there. we are estimating in colombia we have about 30,000 species, but still probably 6,000 new species to be discovered. so you think that there are new species out here in these forests that could actually vanish before they are even discovered? yes, absolutely. and we still don't know the uses of many species. some of the species could have the properties to cure important diseases for humans. and so as biologists, as botanists, we need to understand as much as possible as quick as possible of this amazing biodiversity.

this is like a supermarket, or a pharmacy, and we don't know it, we don't appreciate the forest. 0ur quality of life relies on the preservation of these environments. in the fight to save the forests, the colombian government has extended its protection to millions of acres of land. the army launched 0peracion artemisa in 2019 to combat illegal logging. colonel hermida has a thousand troops deployed in the area. what effect has this had on deforestation here?

but this can't really apply to the whole of colombia, because deforestation is continuing throughout the country — i mean, even here, they are still doing it. this region, colonel, seems very secure, very peaceful but of course in the past, it wasn't like that. do you worry that if they don't find proper alternatives

for people to make a living, that this region will go back to conflict? under colombian law, illegal deforestation carries a sentence of up to 12 years in prison.

but in remote places, the law is hard to enforce. illegal loggers are still at work in these forests.

the loggers say they have bills to pay. they've chosen their target — an 80—year—old rosewood tree. chainsaw whirrs.

this fallen giant will make the loggers $300.

these valleys are populated by miners and loggers. in the town of 0tanche, members of the community have been invited to a workshop organised by the authorities. they hope ecotourism will be the silver bullet, providing an income for the community while saving the forest. the botanists from kew have been invited to make their case.

the fact that there is such a good turnout here — better than expected — shows there is a lot of interest in alternatives to cutting down the forest. but the question is, is it going to give people enough of a livelihood? and that's a big question. the colonel has turned up. sitting next to him is edemildo, who's been a logger all his life. now, though, he is looking for new opportunities.

lidia is one of the pioneers of ecotourism. she set up a butterfly sanctuary to try and entice tourists into the region. it is a natural destination for ecotourism but there is no infrastructure for it at all. it's going to take years, isn't it? and by then, the forest will be almost gone. are you optimistic or pessimistic? are you going to win this fight

to save colombia's natural heritage? for future generations and the environment, time is running out. the need for a solution is urgent. i'm back on the horse, on another field trip with the botanists — this time on rather more even ground. wow! oh, my god! it's like... this is incredible! of all the wild, remote places i've been to in the world, i think this is got to be right up there near the top and as a disabled person, as somebody who can't walk, who has to use a wheelchair,

it's amazingly liberating that here, amongst all this rare flora and fauna, these beautiful butterflies and rare plants, there's this amazing biodiversity. the scientists from kew remain hopeful of finding hidden treasures, before it's too late. it is a very unusual plant. i have never seen it before. i have no idea what genus it belongs to. the thing about plants, they can be rare and special. they all look the same but it's just when you go back and start comparing them with others, you find out how important they are. mauricio, do you think you can persuade people to stop cutting down the forest soon enough before the forest is gone? that's very hard to say. that's our hope and that's our mission — that's why we are here. i believe that we can make a change,

we just have to do our best to protect the best of this biodiversity. jennifer is a local botanist. she's exploring new areas of her country for the first time. how optimistic or pessimistic are you that you, and others like you, who care about nature, who care about biodiversity, that you can save this forest? it's great that you're optimistic, but the reality is the area of forest is getting smaller every year.

colombia today is a post—conflict nation, but it faces a new battle to protect its natural resources. the biodiversity contained in these forests could prove to be its most precious commodity of all.

thanks for tuning into our weather for the week ahead. and the clue is in the bright sunshine. there is a brief hot spell on the way, not quite a heat wave because it won't last for long enough, but temperatures certainly will be skyrocketing — for september — across some parts of the country. we will talk about that in just a second, first, i want to point out this rather long weather front stretching almost from the eastern seaboard of the us across the north atlantic and reaching our shores they are just off western scotland. now, that is going to bring a spell of very wet weather, especially to the western isles of scotland. there will be some rain

in northern ireland, the southwest of scotland may be lancaster, but the heaviest of rain will fall here in the western isles. elsewhere across the country, early on sunday morning, it's actually going to be clear for southern counties, the southeast and east anglia. back onto that wet weather then, and notjust rain but also some very strong winds, possibly gusting around 50 mph. now, this yellow triangle indicates where we could see up to 100 mm of rain. so that means it will be very persistent year through the course of the weekend. it will be very persistent here through the course of the weekend. 15 degrees in stornoway, look at those temperatures starting to rise in the southeast — up to 25 in the sunshine in london and 26 and norwich. now, let's talk about the hot weather then. so high—pressure is dominating the weather across europe, the winds blow in a clockwise fashion around the high. so that means any air in here across spain and france is going to be pushed to the uk. it's also hot, dry air. so plenty of sunshine for england, wales, much of scotland too.

a bit more cloud and maybe some rain in the western isles, and also, here, it's good to be cooler. so no heat here in glasgow and belfast, more like 20. but 30 in london, how rare is that for september? last time, we got 30 or more was actually four years ago, so it doesn't happen that often. so, very warm for the time of year. again, tuesday is going to be another very, very warm, if not hot day, in the southeast — up to around 30 or so. temperatures in the low 20s in northern ireland and also scotland. so how long is this heat going to last? well, it's still going to be quite warm on wednesday, but by the time we get to thursday and friday, it will tend to cool off. and there's not going to be much rain around this week, maybe some across northwestern parts of the uk. let's talk about next weekend, and next weekend does depend on the jet stream — which is the wind that blows high in the atmosphere. it also depends on tropical storms in the tropics. i'm going to show you where the tropical storms are at the moment. there are a whole plethora

of tropical weather here. this one is called paulette. this blue blob here, that's the actual track of the storm over the next few days. and, actually, towards the weekend, the thinking is that paulette will be drifting into our latitudes. now, this next graphic is going to be a little complicated, so bear with me. these are the winds close to the ground. here, further north, i'm going to overlay the jet stream now, so that's at about 30,000 feet, are ten km or so. and when this happens, when these tropical storms, the old ones drift northwards, they tend to interact with the jet stream, and sometimes the jet stream points in a different direction, and that will depend or have a big factor on what sort of weather we are going to get here in the uk. so a little open to debate exactly what we will get next weekend. for now, let's enjoy the warm sunshine.

0xford oxford university and astrazeneca restructure clinical trials of coronavirus vaccines which was halted after a volunteer fell ill. the design and habitat founder who revolutionised british decor and dining has died aged 88. we will ta ke dining has died aged 88. we will take a look at the papers with our reviewers, stay with us for that.