2 . On Tuesday, Virgin Atlantic flew a large passenger jet from London to New York using 100% “Sustainable Aviation（航空） Fuel（SAF）”. The flight was meant to show that it’s possible to fly using cleaner fuels.

The fuel used on the flight was mainly made from used cooking oils and animal fats. A small part of the fuel was made from corn waste. Virgin Atlantic says that using SAF cuts the flight’s pollution by 70%. SAF still pollutes when it’s burned, just like regular jet fuel. However, the difference is in how the fuels are made.

SAF is made from plants （and related animal products） that once absorbed carbon dioxide （CO₂） from the air. When SAF burns, it just releases this same CO₂ again. That’s different from jet fuel, which is made from oil exploited from underground, releasing CO₂ that was deeply buried.

SAF may sound great, but it still has many problems. For one thing, SAF costs five times as much as regular jet fuel. That helps explain why only one-tenth of 1% of the fuel airlines currently use is SAF. Virgin Atlantic is hoping that its flight will encourage more companies to produce SAF and that this will bring the price down.

But even if the price of SAF drops, critics say there are still big problems with it. They say it’s easy to make small amounts of SAF out of plant waste. But to make as much SAF as the airlines really need would require farmers to grow plants for fuel instead of for eating. This could also lead to more forests being cut down for farmland.

Airlines like SAF because it can be used now in existing planes with no changes. They hope it will help quickly reduce airplane pollution until non-polluting fuels are developed.

Governments seem to agree that SAF is a step in the right direction. Both the United States and the European Union have set targets that will sharply increase the use of SAF in coming years.

7 . Most people, if you quizzed them, probably wouldn’t know how much of all global trade is done by sea. It’s one of several reasons that the pollution and carbon emissions from shipping gain much less attention than those from road transport and other industries. It’s over the horizon, out of sight and out of mind.

Today, the international shipping industry is the main mode of transport for around 90 per cent of world trade. It’s powered almost entirely by fossil fuels. Studies show that alternative technologies and zero-emission fuels — including electrofuels such as hydrogen, ammonia and methanol — have the potential to significantly reduce the industry’s carbon footprint and thus require urgent implementation (实施). There’s just one catch: they don’t exist yet.

Even if the technology were available, the infrastructure (基础设施) for that technology or fuel is going to take time to develop. And an even bigger challenge is going to be whether that methanol or ammonia fuel is green, which touches on other industries such as renewable electricity. Do we even have enough renewable electricity in the world to be able to generate these fuels? It’s a complex supply chain that requires cooperation across the industry. It’s not something that one company can solve by itself.

According to Piotr Konopka, senior manager for energy and decarbonisation (碳减排) programs at DP World, there are some simple behavioral changes that can help cut down on fuel used in the meantime, from the regular maintenance and reduced idling of port equipment to the implementation of weather routing that helps ships avoid rougher, more fuel-intensive stretches of water. “Of course, efficiency is unlikely to ever reduce emissions by more than five or ten per cent, but it’s definitely a low-hanging fruit,” he says.

“This is the last moment for the IMO to act decisively to eliminate shipping emissions” says Delaine McCullough, shipping emissions policy manager at environmental NGO Ocean Conservancy. “We need countries to demand that the IMO set strong emission-reduction goals and take action at home if the IMO fails to do the right thing.”

8 . The French couple, Katia and Maurice Krafft, shared an attraction to volcanoes, one that perhaps approached an addiction. There are many people interested in volcanoes, but very few who are willing to climb an erupting crater(火山口) and approach the flowing lava(岩浆). Katia and Maurice did a lot of work, shooting photographs and films of volcano eruptions, always being the first on the scene of an active volcano, and the ones who fearlessly came to just a few feet from lava flows. They were not only highly respected by volcanologists all around the world, but also envied.

The couple metinthe1960s when they were both students at the University of Strasbourg, and got married in 1970. Both of them were attracted to volcanoes since childhood. Upon graduating, Katia and Maurice pursued their careers as volcano observers with no financial support at all, just their own savings, which they spent on a trip to Stromboli to observe the eruption of the volcano.

They took an incredible and valuable set of photographs of the near-continuous eruption. People were curious about the photographs, while public officials working on threatening volcanoes found them useful. This interest in their work helped the French couple to establish a career in documenting eruptions. Now able to obtain financial support for their work, Katia and Maurice visited hundreds, if not thousands, of volcanoes around the globe. They traveled and recorded eruptions, always getting closer to the danger than anyone else.

In June 1991, along with 40 other people, the Kraffts set out to film the eruption at Mount Unzen in Japan. A sudden and unexpected flow took place and all the people in its path were killed. Later investigation revealed that Katia’s and Maurice’s bodies were closest to the volcano crater. They were 44 and 45 years old respectively.

In their 25-year-long career, the couple documented hundreds of volcanoes, and their work consists of thousands of sill photos, 300 hours off film materials, a number of books, and scientific articles published in Bulletin of Volcanology.

10 . A forest after a wildfire

Throughout my career, I’ve had many chances to enter various wildfire areas. But I’ve ________ had the opportunity to see the immediate scene after a fire.

So when I ________ into a recently burned forest, my first reaction was the deathly ________ hung in the air. There were no birds, no breeze caught in the leaves of a tree, or animal noises. It felt as if life itself had totally ________ from this place. What was even worse, the burned-out forest meant that a large amount of ________ alongside the road was no longer ________ by the under-growth (灌木丛) . Oil cans, glass, plastic bags—you name it, and you can find it.

Knowing there was a story here that needed ________ , I raised my camera with a heavy heart, no matter how ________ . Photographing burned-out areas is ________ , since there is really only a bunch of burned-out wood. Through my lenses, I sought to connect viewers to the ________ of the disaster.

For a nature photographer passionate about environmental protection, it’s important to ________ the ugly as well as the beautiful. We need to put those two things together, so while ________ hope, we are aware of what has been taken from us, and how ________ that loss can be. Without that balance, we risk becoming used to a world shaped by destruction and not the one of ________ . Nature will regenerate, but now, we must consider what ________ we humans play in that process, too.