3 . Five years ago, we cut nearly every single tree across 19 acres here, piled and burned the branches and left the trunks where they lay. The goal was to restore one of the Ozarks’ rarest ecosystems, a type of dry and rocky grassland.

Logging down trees to bring back grass may seem puzzling in a time of climate change, as forest conservation and tree planting have become popular ways to keep carbon out of the atmosphere. But it is exactly what we should do in some parts of the Southeast. The climate and biodiversity crises are problems to be solved together. We can’t afford to rob biodiversity to pay for the climate. And grasslands are surprisingly good at pulling carbon out of the atmosphere. A single sunflower might not be the carbon grab that an oak tree is, but grass’s deep root systems store the element deep underground, where it can take hundreds or thousands of years to return to the atmosphere.

For the past century, the commonly held belief was that forests once covered most of the region from the Atlantic Ocean to the Mississippi River. But we now know that’s not true. Much of the Southeast was a string of large and small grassland ecosystems with enormous biodiversity. All of these unique grasslands are under threat, but not all by tree invasion. The few remaining grasslands in Arkansas are being converted to grow rice, Virginia grasslands are being flattened by housing developers, and low-lying coastal grassy plain is facing sea-level rise. Because grasslands are so easily navigated (导航) and settled, they may be the most threatened ecosystems in the world.

And it’s obvious that everywhere, grasslands remain undervalued. Many conservation organizations working in the Southeast are still focused on tree planting and preserving existing forests. The Nature Conservancy’s Cumberland Forest Project covers 253, 000 acres of land in Kentucky, Tennessee and Virginia, part of an effort to store carbon and create continuous habitats for species migration during climate change. In fact, recent laws are beginning to lead us in the right direction.

4 . With greater climate catastrophe (气候突变) on Earth, it is natural for us to make every effort to stop the potential floods, snowstorms, and alarming reports from scientists. For many of us (myself included), part of that means running out to buy reusable straws, organic cleaners, and packaging-free products.

However, before you rejoice in “green” purchases, take a second to consider the results of a new study from Arizona University. By comparing the shopping habits, mental health and environmental impact of young people, the researchers reaffirmed a principle: Buying less beats buying “green” stuff without effort. And that is true whether you are looking at the impact that your purchases have on the Earth or on your own happiness.

It should not come as a shock that simply consuming less is better for the planet. After all, every new item a factory yields requires some resources to produce. Take plastic bag bans for instance. If your city is getting rid of single-use shopping bags, it can be tempting to pay for a fashionable organic cotton bag hanging in the check-out line of your local supermarket. However, experts insist that growing cotton is actually no better for the Earth than producing the conventional plastic bags. Your best bet for carrying your groceries if you care about sustainability? Any bag you already own. This is true of many kinds of “green” products.

It is not just the Earth that will be happier if you buy less. You will feel more contented too, according to the new study. “People believe that they might well be self-satisfied about becoming environmentally conscious through green buying patterns, but it doesn't seem to be that way”, said the lead researcher Sabrina Helm. “Reduced consumption has effects on increased well-being and decreased psychological distress, but we don't see that with green consumption.”

“Owning every new green product on the market might make you feel contented, but if you relieve yourself of that burden of ownership, most people report feeling a lot better,” said Helm.

6 . Washing machines are one of the greatest inventions of the last few centuries.They have made life easier. Unfortunately, washing machines also contribute to the environmental issues of energy use and micro-plastics flowing into the oceans. That is why the washing machine manufacturer (制造商), Samsung, and the outdoor-wear company, Patagonia, are working together to make a change.

For Patagonia, the issue of micro-plastics has been on its mind for years — its woolen jackets release many microfibers. As for Samsung, new requirements throughout the world have forced many producers to start thinking about ways to help reduce the number of micro-plastics. There are currently more than 14 million tons of micro-plastics floating in the oceans. Though people previously think of things such as plastic bottles and fishing lines when it comes to plastics in the ocean, thousands of micro-plastics are released into seas with every wash.

The issue is a sort of catch-22. In order to reduce energy costs, manufacturers try to make their machines more efficient. These machines use hotter water and are designed to create more friction (摩擦) between the clothing in the machine. However, both of these things lead to the release of more micro-plastics. So, using Patagonia clothes as test cases, Samsung came up with a two-fold solution: One is a technology called Eco-bubbles, which creates more bubbles to make the detergent (洗涤剂) more powerful, and the other is a water purifier that can filter (过滤) out more micro-plastics.

The cooperation between the two companies is proof of how complicated protecting the environment can be. On the one hand, clothing that is well-constructed and durable is a weapon in the fight against fast fashion. On the other hand, the material used to make those clothes and the way they are washed can also add pollutants to the environment.The same goes for washing machines. There is no one-size-fits-all solution. The fight against climate change requires creative thinking and learning how to attack a problem from many angles. This will certainly lead to even more strange and fruitful cooperation between the environmentally conscious companies.

8 . For 30 years we have been told how temperatures have been rising rapidly to unheard of levels. This is causing polar ice to melt, sea-levels to rise and has brought about a dangerous increase in extreme weather events. These intense climatic changes would likely present challenges to our society and environment.

The causes of climate change are mainly anthropogenic (人为的) in nature. Since the industrial revolution, human activities have increased the amount of greenhouse gases in the atmosphere. The increased amount of gases which absorb heat has led to more heat being kept in the atmosphere, causing global warming.

The certainty of global warming can be seen through some of the natural phenomena like the effect on crops and extreme weather conditions around the world. The most recent assessment report says that the earth’s average temperature has risen by 0. 74 degrees in the period from 1906 to 2005, and that the average temperature will continue to rise. There have also been more violent downpours, sea levels have risen and the ice at the world’s poles and on its mountains is melting. The rising sea level is flooding the low-lying countries in Asia and small islands in the Pacific. This may lead to the displacement of millions of people, loss of millions of land and consequently billions of dollars.

Troubled by the serious situation, world leaders came together for the 2015 United Nations (UN) Climate Change Conference in Paris. The climate talks led to 196 countries reaching a landmark agreement that will, for the first time, commit nearly every country to lowering planet-warming greenhouse gas emissions to address global climate change. That was certainly an encouraging step forward for our earth and mankind!

As the world leaders continue to commit themselves to monitor our sick planet, we need to continue to take small steps to heal the world. We are left with not much of a choice. If only we could just pack our bags and migrate to Mars!

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9 . Typhoons can be deadly — in 2013, Typhoon Haiyan, the strongest ever recorded, was responsible for 6,340 deaths—and cost billions in damages. Current forecast models can only predict these storms 10 days in advance, at most, and they cannot precisely predict how intense the storms will become.

An international team of researchers has developed a model that analyzes nearly a quarter of Earth’s surface and atmosphere in order to better predict the conditions that birth typoons.

“The target problem of this study is how to foretell the birth of typhoons,” said paper author Mingkui Li, associate professor in the Key Laboratory of Physical Oceanography in the Ocean University of China and the Pilot National Laboratory for Marine Science and Technology (QNLM). “We specifically address three aspects: the beginning time, inner pressure and maximum wind speed.”

The researchers also accounted for the influence of one variable(变量) on another, such as wind speed on sea surface temperature. This influence is well understood and accounted for in climate predictions and in weather forecasts, but it has not been fully applied in understanding how long-term climate affects day-to-day weather, according to Li. “We aimed to provide insights on the time scale that can be used to forecast typhoons in advance.”

From their study, the researchers determined that a model with the ability to better understand the relationship between warm sea surface temperatures and weak wind movement— conditions that favor typhoon formation—could improve typhoon predictability.

“Our goal is to develop a 10 to 30-day prediction system that will lead to seamless(无缝的) weather-climate predictions.” Shaoqing Zhang, paper author and professor in the Key Laboratory of Physical Oceanography, said.