2 . Carbon dioxide emissions from transportation are now thought as the top source of green-house gases. One of the most effective ways to reduce your carbon footprint is to reconsider how much, and how often, you travel.

Going car free for a year could save about 2. 6 tons of carbon dioxide, according to a study from the University of British Columbia. How can you stop using a car? Try taking a train, bus or better yet, riding a bike.

But let’s be realistic. You will likely need to use a car this year. So, when you do, here are some tips to make your trip more climate-friendly. Driving efficiently can help to reduce emissions. Go easy on the gas and brakes and drive like you have an egg under your foot. Regularly service your car to keep it more efficient. Keeping your tires pumped correctly can re-duce emissions. Low tire pressure will hurt your fuel economy. Air conditioning and frequent city driving can make emissions go up. So cut down on these as often as possible. Use cruise control (定速巡航) on long drives-in most cases, this can help to save gas. Don’t weigh your car down with extra things that you don’t need on your trip.

Fly often? Taking one fewer long round-trip flight could reduce your personal carbon footprint significantly. If you use public transportation often and fly less, your carbon foot-print might still be relatively sustainable, but if you drive and fly a lot, your emissions will be sigher. If you can’t avoid flying, you can offset them by donating money to sustainable proacts, such as supplying efficient stoves to rural homes, or projects which help farmers deal with crop waste environmentally.

3 . As a young girl growing up in France, Sarah Toumi dreamed of becoming a leader who could make the world a better place. Her passion to help others was awakened when, from the age of nine, she accompanied her Tunisian father to his birthplace in the east of the country during holidays. There she organized homework clubs and activities for children.

Toumi witnessed first-hand the destructive effect of desertification (沙漠化). “Within 10 years rich farmers became worse off, and in 10 years from now they will be poor. I wanted to stop the Sahara Desert in its tracks.” A decrease in average rainfall and an increase in the severity of droughts have led to an estimated 75 percent of Tunisia’s agricultural lands being threatened by desertification.

Toumi recognized that farming practices needed to change. She is confident that small land areas can bring large returns if farmers are able to adapt by planting sustainable crops, using new technologies for water treatment and focusing on natural products and fertilizers rather than chemicals.

In 2012, Toumi consolidated (巩固) her dream of fighting the desert. She moved to Tunisia, and set up a programme named Acacias for All to put her sustainable farming philosophy (理念) into action. “I want to show young people in rural areas that they can create opportunities where they are. Nobody is better able to understand the impact of desertification and climate change than somebody who is living with no access to water.”

By September 2016, more than 130, 000 acacia trees had been planted on 20 pilot farms, with farmers recording a 60 percent survival rate. Toumi estimates that some 3 million acacia trees are needed to protect Tunisia’s farmland. She expects to plant 1 million trees by 2018. In the next couple of years, Toumi hopes to extend the programme to Algeria and Morocco.

5 . An environmental group in Colombia is leading a project to save wild areas in the San Lucas Mountains with the help of coffee growers.

Since 2016, San Lucas areas have been threatened by mining and coca (古柯) planting Gold miners and coca growers make more money than coffee farms. Now the group WebConserva helps link coffee farmers with coffee processors from around the country in order that they can earn more. At the same time coffee farms can serve as boarders around the forests to protect the biodiversity within.

To date, the project includes 10 families who farm 400 hectares of coffee plants. WebConserva said it hopes, in time, 200 families will be included. At that level. 20,000 hectares of untouched forest could be protected. The families promise not to cut down trees to expand their crops or to hunt wild animals. In return, they receive $300 for 125 kilograms of coffee.

Arcadio Barajas is among those taking part. His coffee farm sets up a barrier between cattle farms and forests where wild animals live, thus reducing the possibility of conflict between cattle farmers and wild animals.   “Cutting down the forest to plant coca and killing wildlife were against my faith, and now I feel that growing coffee lets me be a good guard of the land,” he said.

Amnobis Romero is a former coca grower and miner. “Many families depended on illegal activities to support their children years ago. Now, we feel it a duty to look after this biodiversity and leave it for future generations,” he said. Activists want San Lucas to be protected as a national park, but the process has been slow. Carlos Valderrama, director of Webconserva, hopes the project can build production system that will last far into the future. “It protects forests, biodiversity and ecosystems at the same time as improving coffee growers’ quality of life,” he said.

8 . A new analysis of photographs from the International Space Station has identified a shift in the kind of lighting technologies that European countries are using at night to brighten streets and buildings. Researchers have found that the old warm high-pressure street lights are rapidly being replaced by cooler LED lights. The University of Exeter study, published in Science Advances, claimed that “this phenomenon is widely increasing the risk of harmful effects to ecosystems”.

LED lighting was promoted as being intended to reduce emissions, but its usage has raised energy consumption. One explanation of this is that the increase in power efficiency and the associated decrease in economic cost have driven increased demand for lighting, therefore, any efficiency gains have been counteracted by increased consumption of light.

The study also claimed that previous research into the effects of light pollution have underestimated the impacts of blue light radiation. Chief among the health consequences of blue light is its ability to reduce the production of melatonin(褪黑素)that regulates sleep patterns in humans and other organisms. Scientific studies have warned that increased exposure to artificial blue light can worsen people’s sleeping habits.

The increase in blue light radiation in Europe has also reduced the visibility of stars in the night sky, which may have impacts on people’s sense of nature. Blue light can also alter the behavioral patterns of animals including bats and moths, as it can change their movements towards or away from light sources.

David Smith, of the conservation charity Buglife, said, “Light pollution can dramatically impact animals. We should consider light from a wider biological perspective than that of just humans and focus on better quality lighting that is harmonious with our natural world. Better quality and lower levels of lighting would help save energy, and lower financial costs, while also making our environment safer for living beings. Authorities can dim the lights during night hours, and change the bandwidths(带宽值)of their LED bulbs to produce less harmful blue light.”

10 . With an abundance of sun and wind, Spain is positioning itself as Europe’s future leader in green hydrogen production to clean up heavy industries. But some energy experts express caution because this process relies on massive availability of zero-carbon electricity.

Green hydrogen is created when renewable energy sources power an electrical current that runs through water, separating its hydrogen and oxygen molecules (分子). The process doesn’t produce planet-warming carbon dioxide, but less than 0.1% of global hydrogen production is currently created in this way.

The separated hydrogen can be used in the production of steel, ammonia (氨) and chemical products, all of which require industrial processes that are harder to stop fossil fuels. Hydrogen also can be used as a transportation fuel, which could one day transform the highly polluting shipping and aviation sectors.

Spain’s large, windswept and thinly populated territory receives more than 2,500 hours of sunshine on average per year, providing ideal conditions for wind and solar energy, and therefore green hydrogen production.

“If you look at where hydrogen is going to be produced in Europe in the next million years, it’s in two countries, Spain and Portugal,” said Thierry Lepercq, the founder and president of HyDeal Ambition, an industry platform bringing together 30 companies. “Hydrogen is the new oil.”

Lepercq is working with companies like Spanish gas pipeline corporation Enagas and global steel giant ArcelorMittal to design an end-to-end model for hydrogen production, distribution and supply at a competitive price. Criticism has centered on green hydrogen’s higher cost compared with highly-polluting “gray hydrogen” drawn from natural gas. Lepercq argues that solar energy produced in Spain is priced low enough to compete.

Globally, Lepercq said, “Electricity is 20% of energy consumption. What about the 80% that is not electrified? ... You need to replace those fossil fuels. Not in 50 years’ time. You need to replace them now.”