Hey, I'm Carl Azuz.
Today on CNN STUDENT NEWS, pollution around the world, a mirage that may be a mirage and a ghastly ghostly drone.
First up, an international trip by a Middle Eastern leader.
Syrian President Bashar al Assad travelled to Moscow this week.
Officials believe it's the first time that al Assad has left Syria since its civil war started in 2011.
He went to the Russian capital to meet with the man who's become his main sponsor, Russian President Vladimir Putin.
Russian officials say the two leaders discussed working together to fight terrorist extremist groups.
That's a term the Assad regime uses to describe anyone fighting the Syrian government.
Russia says its military is in Syria both to fight terrorism and to help the Syrian government stay in power.
In the four and a half years since the war in Syria began,the human rights group Amnesty International says 200,000 people have been killed and that 11 million people, that's almost two-thirds of Syria's entire population, have been forced to flee their homes.
Today's "Roll Call" starts near the Caribbean, with the city in northwestern Venezuela.It's Maracaibo.
And we found out yesterday that students of Escuela Bella Vista are watching there.Great to see you.
Next, we're moving north to north Georgia, and flying with the Falcons of Flowery Branch High School.
Hello to our viewers in Flowery Branch.
And a little further north, in northeast Illinois, shoutout to Elmwood Park High School.It's in Elmwood Park, not too far from Chicago.
Ahead of the climate conference in Paris next month, the number of international officials are calling for a price in carbon.
Carbon dioxide emissions are blamed for pollution worldwide.
A carbon price or carbon tax would require certain organizations or businesses to pay a fee.
The more carbon their projects gave off, they more they'd have to pay.
Supporters say this would encourage countries to reduce their carbon emissions, to look for cleaner ways to make products and do business, and to generate revenue that could be used to clean up the environment or research green technologies.
But opponents of the idea say some businesses would simply move their operations to other countries where there isn't a carbon tax to avoid paying it.
They also say it will be expensive to institute carbon taxes and carbon monitoring and that some corporations could cheat to get around the fees.
CNN has reporters all around the world and several recently discussed ways to combat pollution in the cities where they work.
We start in Hong Kong.
I'm Ivan Watson in Hong Kong, where some of the city's 7 million residents are choking on the air they breathe.Cases of chest infection and asthma have soared in recent years, and the problem has caused more than 2,600 premature deaths in 2014, according to a report by the University of Hong Kong and cost the economy nearly $4 billion.
Think tank the Civic Exchange says 98 percent of the worst pollutants in the city's air come from commercial shipping and ferries.
In July, introduced landmark new rules limiting the sulfur content of the diesel used by ships to half of 1 percent.
And after a nightfall of that, a typical early morning often looks like this.
You can barely see more than a dozen feet ahead of you.
Now, trucks aren't allowed to fly these roads during the day, but cars are.
And the sheer number of cars is a problem.
Every day, 1,400 new cars join the 8.5 million already on the streets here.
The World Health Organization has labeled India's capital the most polluted city on the planet.
Policymakers are beginning to react, with New Delhi's government trying out what it's calling a car-free day.
Delhites will be encouraged to leave their cars at home and instead take public transport.