Venice is suffering the worst flooding the city has experienced in 50 years. The city is “on its knees” and Venetian Mayor Luigi Brugnaro tweeted as water submerged (淹没) much of the famous historical city.

While floods are a normal part of life in Venice, they have never happened with such frequency before. Experts say that climate change is likely to blame. 【小题1】 The Venetian council voted against a measure to fight climate change just a few moments before their chamber (会议厅) flooded.

Flooding is just one of the many impacts from climate change that is being experienced with more frequency and globally threatens many vulnerable (脆弱的) areas and regions. There is a threat that is not often considered. 【小题2】 Natural and man-made heritage sites throughout the world are in danger of being damaged or destroyed by climate change.

【小题3】 Some will be hit by flooding, like Venice, others by extreme weather events or rising temperatures. For instance, George Town, the capital of the Malaysian state Penang faces rising sea levels, landslides and more severe typhoons, while Yellowstone ecosystem in the western United States faces melting snows, more frequent wildfires and a changing ecosystem.

Changes in the ocean will have a profound impact on many of these sites. 【小题4】 And rising sea levels threaten to wash away many of the world’s great archaeological sites.

Experts say that the solutions to saving these sites will be varied, but many will be very expensive. 【小题5】

Torrential rains have hit China In July, with 617.1mm of water reportedly falling form Saturday to Tuesday in Zhengzhou, for which more than 100,000 people have been evacuated. The scenes of devastation(破坏)in Zhengzhou added to a list of disasters this year that have raised the fear of climate change.

As the effects of climate change become more disastrous, well-known research institutions and government agencies are focusing new money and attention on an idea: artificially cooling the planet, in the hopes of buying humanity more time to cut greenhouse gas emissions.

That strategy, called solar geoengineering, involves reflecting more of the sun's energy back into space to abruptly reduce global temperatures. The idea has been considered as a dangerous and fancied solution, one that would encourage people to keep burning fossil fuels while on the other hand exposing the planet to unexpected threatening side effects, producing more destructive hurricanes, wildfires, floods and other disasters.

But as global warming continues, producing more destructive hurricanes, wildfires, floods and other disasters. some experts say that concerns about geoengineering should be outweighed by the imperative to better understand it, in case the consequence of climate change become so terrible that the world can't wait for better solutions.

One way to cool the earth is by injecting aerosols(气溶胶)into the upper layer of the atmosphere, where those particles(粒子)reflect sunlight away from the earth. That process works, according to MacMartin, a researcher at Cornell University.

“We know with 100% certainty that we can cool the planet,” he said. What's still unclear, he added, is what happens next. Temperature, MacMartin said, is an indicator for a lot of climate effects. “What does it do to the strength of hurricanes?” he asked, “What does it do to agriculture production? What does it do to the risk of forest fires?”

Another institution funded by the National Science Foundation will analyze simulations of aerosol injection, testing the effects on Weather extremes around the world. One goal of the research is to look for a sweet spot: the amount of artificial cooling that can reduce extreme weather events without causing broader changes in regional rainfall patterns or similar impacts.

Food made from atmospheric carbon could feed the world while helping to fight climate change, according to Solar Foods, a Finnish company founded in 2017.“We can collect CO2 anywhere,” said its CEO Pasi Vainika, whose company has developed a protein powder made using CO2. “That’s a strategic shift where raw materials are in the air. ” The protein powder, called Solein, can be turned into meat and dairy substitutes or added tofoods and shakes.

Solar Foods uses special units to pull CO2 from the atmosphere. To turn it into protein,microbes (微 物),similar to those in the production of wine and yogurt, will be fed on it to grow and reproduce. During the process, water is split into hydrogen and oxygen. Along with a growth medium containing necessary minerals, the three gases are pumped in to feed the microbes. Harvested and dried, that remaining mixture becomes Solein—a yellow powder made up of single-cell protein, with a nutrient composition similar to wheat flour.

Solar Foods claims that Solein removes most of the emissions associated with modern agriculture, which is responsible for almost one-third of all greenhouse gas emissions. “One kilogram of Solein sends out 0.2 kilogram of CO2e(二 氧化碳当量).In comparison.beef herds produce around 100 kilograms and chicken 10 kilograms,” said Vainikka. “ We can rermove the climate impact of modern food systems on the planet, which today account for about 30 per cent of global greenhouse gas emissions.” He further stressed that while the company’s factories also require some land used for industrial farming, only about one-tenth of the land is needed compared to photosynthesis (光合作用）. “We could free up agricultural land to grow back forests,” he added, “and those remove carbon permanently from the atmosphere.”

Probably optimists are now contenting themselves with the pleasant scene of masses of trees absorbing CO2: on the planet. However, while that may sound great, Vainikka put it right, “It can happen only if we produce enough Solein from CO, to replace meat and dairy at a large scale.”And that still remains a long way to go.