2 . Among the world’s waste-recycling pioneers, Germany is the leader. The country has quite a detailed way of sorting their waste-down to the color of glass waste, the type of paper, the separate bin for metals, etc.

Here below are what you should know about Germany’s waste sorting system：

◇You are expected to gather your waste in your apartment/housing area’s local public garbage bins.

◇There are commonly several types of public garbage bins available in the German’s apartment/housing areas：

Blue bin — for paper and cardboard

Green and white bin — for glass, different bins for differently colored glass, not available for holiday decorations and lights

Yellow/orange bin — for plastic and metals

Brown bin — for goods that can be changed naturally by bacteria into substances that don’t harm the environment, like leftovers, fruit and vegetables

Gray/black bin — for everything else that can’t be recycled such as used cat litter and animal waste

◇Some items don’t belong in these public garbage bins. Items like used batteries, electronics, unused paints, and lights must be returned to the special agent/locations so they can be properly recycled. Other items such as clothes, shoes, and oversized rubbish and furniture are advised to be donated or sold.

◇There’s this thing called Pfand in Germany, a certain part of the price for a bottled drink that you get back if you send back the bottle to certified (有资历的) shops. German law requires shops over a certain size selling bottled drinks have a Pfandruckgabestelle, or place for bottles with deposits (押金). These bottles usually made of glass or plastic will be refilled. Of course, there’re strict health regulations.

4 . Extreme heat often brings extreme wildfires, and this year is no exception, with unprecedented heat waves fueling enormous outbreaks of fires in the western United States and Canada as well as across the Mediterranean and in Siberia. But paradoxically the most intense wildfires can have the opposite effect on temperatures, cooling Earth’s surface both regionally and globally.

Dense wildfire smoke can temporarily block sunlight near the ground, causing regional temperatures to drop by several degrees. Wildfire smoke can also have global cooling effects by making clouds in the lower atmosphere more reflective or blocking sunlight in the upper atmosphere, similar to what a volcanic eruption does.

The effect is far too small to counteract（抵制，抵消）human-caused global warming; researchers say it’s too early to predict what it means for the broader climate system. But with fire seasons growing more intense around the world and triggering a range of extreme fire weather in North America and elsewhere, the search for answers is growing increasingly urgent.

Smoke particles act as seeds for water vapor to form clouds that are smaller and reflect more sunlight. While smoke tends to rain out of clouds fairly quickly, the Australian bushfires raged for months, pumping more and more cloud-brightening smoke into the atmosphere. “It’s not a big effect, but when you integrate over the entire Southern Ocean. it adds up” one of the researchers says.

While this research highlights the cooling effects of smoke in the lower atmosphere, on occasion, wildfire smoke can reach even higher altitudes into the stratosphere, the layer that starts about 10 miles up. There, it can have additional effects on the climate. Smoke reaches the stratosphere when heat from a powerful wildfire creates an updraft that combines with moisture in the atmosphere to generate towering thunderclouds.

However, scientists have only recently begun studying these effects. “We might still be in the infancy of understanding how large and how important the effects of these wildfires are.” scientists say.

7 . The Unbelievable Survival from Bear Attacks

This past October, I took an early morning hike in the Madison Valley in southwest Montana. Knowing that bears are common throughout the area and not wanting to surprise one, I shouted out, “Hey, bear” every 30 seconds.

About three miles in, I stepped out into a meadow and shouted again. A few more steps and I spotted a brown bear with her babies on the trail at the upper end of the meadow. The sow saw me right away, and they all ran up the trail. But then she stopped, turned, and charged straight to me. I yelled so she would know I was human and hopefully turn back. No such luck. I gave her a full charge of bear spray at about 25 feet. Her momentum (冲力) carried her right through the orange cloud and onto me.

I dived face—first into the dirt and wrapped my arms around the back of my neck for protection. She was on top of me, biting my arms, shoulders, and backpack. The force of each bite was like a hammer with teeth. Over and over she bit me. After what felt like hours but was merely minutes, she disappeared, apparently satisfied that I caused no further threat.

I tried to pick myself up, but my eyes were full of blood and I couldn't see. I knew that if she came back again, I'd be dead, so I wiped the blood from one eye and looked around. No bear. I stood up and moved quickly down the trail again. Forty­five minutes later, I got into my truck and drove 17 miles to the hospital. It took doctors eight hours to treat the wounds on my arms and shoulder. A five-­inch cut along the side of my head will leave a terrible scar.

If you ever find yourself in this situation, know how to protect yourself from a brown bear.

One spring morning may years ago, I had been looking for gold along Coho Creek in southeastern Alaska. I froze in my tracks—no more than 20 paces away in the bog（沼泽）was a huge Alaskan wolf—caught in one of traps.

Confused and frightened al my approach, the wolf backed away. Then I noticed something else: It was a female, and obviously, she was in lactation（哺乳期）. Somewhere there was a den（窝）of hungry pups waiting for their mother. From her appearance, I guessed that she had been trapped only a few days. That meant her pups were probably still alive, surely no more than a few miles away. But I suspected that if I tried to release the wolf, she would turn aggressive and try to tear me to pieces. So I decided to search for her pups instead and began to look for tracks that might lead me to her den. Fortunately, there were still a few remaining patches of snow.

After several moments, I spotted paw marks on a path to the bog. I finally spotted the den at the base of an enormous tree. There wasn't a sound inside. Wolf pups are shy and cautious, and I didn't have much hope of attracting them outside. But I had to try. So I began imitating the cry of a mother wolf calling her young. No response. A few moments later, after I tried another call, four tiny pups appeared. They couldn't have been more than a few weeks old. I extended my hands, and they tentatively suckled at my fingers. Perhaps hunger had helped overcome their natural fear. Then, one by one, I placed them in a bag and headed back to the mother wolf. When she spotted me, she stood straight.

I released the pups, and they raced to her.

I hiked and spotted a dead deer sticking out of a snow bank.