November "Science" Rumors List | Cold weather means a cold winter? Electric cars have higher carbon emissions than fuel cars?

High? Planting a trillion trees can reverse climate change? Come to see the November "Science"

The monthly "science" rumor list is guided by the Beijing Association for Science and Technology, the Beijing Municipal Cyberspace Administration, and the Capital Internet Association, and jointly released by the Beijing Science and Technology Journalists and Editors Association and the Beijing Regional Website Joint Rumor-Refuting Platform, and is supported by the Science and Technology Journalists and Editors Professional Committee of the China Science Writers Association, the China Evening News Science Editors and Journalists Association, the Shanghai Science Communication Association, and the Beijing Institute of Scientific and Technological Information.

1. A winter with extremely cold weather is called a "cold winter".

It’s so cold just a few days into winter. This year must be a “cold winter”.

(Photo source: Cover of Beijing Science and Technology News)

the truth

The perceived "cold winter" is not the same as the meteorological "cold winter". Extreme cold events and cold winters are weather concepts, while cold winters are climate concepts. Even a warm winter may have extreme cold weather events. The complexity of climate forecasting is much higher than that of weather forecasting.

Taking the winter of 2020 as an example, although my country also experienced a moderate La Niña event (referring to the situation in which the sea water temperature in the central and eastern equatorial Pacific Ocean continues to become abnormally cold over a large area. After the La Niña event is formed, the meridional direction of the atmospheric circulation in the mid- and high-latitude regions increases, causing cold air to frequently move south), in March this year, the National Climate Center released news showing that the winter from December 1, 2020 to February 28, 2021 was a warm winter. The reason is that the temperature was high in the second half of the winter, causing the average value to rise.

The average winter temperature fluctuates every year. Temperatures above the average are high, and temperatures below the average are low. However, a slightly low winter temperature does not mean a "cold winter." According to the standards released by the National Climate Center, the basic element for determining a cold winter is the average temperature of the three months of winter, which is spatially divided into three levels: single station, regional, and national. A single station cold winter is defined as one where the average temperature of the station is less than or equal to -0.43 times the standard deviation of the average temperature of the average temperature; if the number of cold winter stations exceeds 50% of the total number of stations in the region, it is defined as a regional cold winter; if the cold winter area exceeds 50% of the effective area of ​​the country, it is defined as a national cold winter. According to this standard, our country has not experienced a nationwide cold winter for more than a decade.

In response to the increase in extreme weather that may come in winter, the public should still pay attention to the weather forecast and warning information from the meteorological department, not blindly believe in online rumors, pay attention to adding or removing clothes in a timely manner, pay attention to temperature changes, and arrange work and travel reasonably.

2. Astronauts gain weight once they arrive at the space station

gossip

Astronauts Zhai Zhigang, Wang Yaping and Ye Guangfu gained weight as soon as they arrived at the space station.

(Photo source: Xinhua News Agency video screenshot)

the truth

Recently, CCTV's "The Reader" released a video of the Shenzhou 13 astronauts reading in space. In the video, Wang Yaping, Ye Guangfu and Zhai Zhigang read excerpts from the general preface of Ba Jin's "Torrent" one after another. Netizens praised it as "poetic from afar" and "cosmic romance". Some netizens also found that the three astronauts looked "a little fatter". Thinking of the astronauts' diet that they had seen before, everyone couldn't help but wonder: Did they gain weight?

This is not the truth! In a state of weightlessness, astronauts' blood will rush to the brain and upper body, and the viscosity of the blood will change, causing facial swelling and even head swelling. However, factors such as food and exercise will not quickly cause such changes.

Previously, some netizens also found that Nie Haisheng, Liu Boming and Tang Hongbo had edema. Therefore, the astronauts' round faces are not because they have gained weight, but a normal phenomenon of blood redistribution in the body under specific conditions. It is not pathological and is fundamentally different from edema on the ground.

3. Electric vehicles cause more total emissions than fuel vehicles

gossip

The pollution and carbon emissions of electric vehicles are not lower than those of traditional fuel vehicles. It is just that the pollution and emissions are transferred to the process of power generation and battery production, which actually makes them higher than fuel vehicles.

(Photo source: Visual China)

the truth

Due to production process reasons, the total carbon emissions of electric vehicles are higher than those of fuel vehicles. But taking all factors into consideration, electric vehicles are lower in carbon emissions.

First of all, the power source of electric vehicles does not entirely come from coal-fired thermal power. my country's hydropower, wind power, nuclear power and solar power and other non-fossil fuel power generation account for nearly 30% in total, that is, 30% of the power of electric vehicles comes from these clean energy sources. According to the requirements of the "carbon peak and carbon neutrality" goals, by 2030, the proportion of domestic non-fossil energy power generation will reach about 50%, and by 2050 it will reach more than 90%. As the proportion of new energy in power generation increases, the carbon emissions of electric vehicles will inevitably show a gradual decline.

Secondly, when calculating the carbon emissions of fuel vehicles, it is also necessary to consider the carbon emissions during the extraction, refining and transportation of oil, which is the same as emphasizing the carbon emissions during the production of electric vehicle batteries. After combining this data, the carbon dioxide emissions per kilometer of medium-sized fuel vehicles far exceed those of electric vehicles.

On the other hand, even if all the energy for electric vehicles comes from coal-fired power plants, pollutants can be greatly reduced, because our country's coal-fired power plant technology can already achieve ultra-clean emissions, and particulate matter, sulfur dioxide, and nitrogen oxides produced after combustion can all be fully recovered. Compared with the disorderly emissions of fuel vehicles, the systematic emissions of coal-fired power plants are obviously easier to manage, and can also be improved overall through technological progress.

In short, when analyzing the gap between the two, we should not only magnify the differences in production, circulation and manufacturing, but also consider the entire life cycle and long emission process. From the perspective of the vehicle's entire life cycle and the general trend of technological development, electric vehicles are undoubtedly lower-carbon.

4. The internet celebrity hangover remedy can help people drink a thousand cups without getting drunk

gossip

Taking a pill of "alcohol sobering magic" can increase your alcohol tolerance and prevent drunkenness. This health food is extracted from pure plants, has no side effects, and can accelerate the decomposition of alcohol, achieving the effect of quickly sobering up and increasing your alcohol tolerance.

(Photo source: TV series "Nothing But Thirty")

the truth

In clinical practice, no drug has been approved by the national drug regulatory authorities for the indication of sobering up. Using some so-called "folk remedies" or "old recipes" to sober up not only fails to sober up, but may increase the burden on the liver and even cause liver damage, which is really not worth the loss.

The so-called "alcohol remedies" on the market are essentially health products or foods. Health foods cannot contain drug ingredients. The vast majority of foods that claim to have liver protection functions and reduce alcohol damage to liver cells usually contain ingredients from Chinese herbal extracts that are both medicinal and edible, such as licorice, ginseng, and kudzu root. Some amino acids are also added, such as L-cysteine ​​and taurine, which are also food additives, but the efficacy of these ingredients is not certain.

After drinking too much and alcohol poisoning, clinically, drugs such as naloxone, nalmefene, and metadoxine can work. For example, "naloxone hydrochloride sublingual tablets" can enter the brain after being taken sublingually, which can relieve the central inhibition caused by ethanol; naloxone cannot be effective if swallowed directly orally, and can only be injected intravenously or taken sublingually in the hospital. It is metabolized quickly and the drug effect can only last for about an hour; it should be noted that when a person is seriously drunk, others should not rashly help the drunk person take medicine, because in addition to the possibility that the tablets may be swallowed directly and cannot be released under the tongue, it is easier to accidentally inhale the tablets into the trachea.

So how do you sober up correctly? The most important thing about sobering up is to promote the excretion of ethanol and alcohol accumulated in the body. On the one hand, you can replenish fluids appropriately after drinking, drink more water, dilute the concentration of ethanol and alcohol in the body, and reduce the burden on the liver; on the other hand, drinking more water can also have a diuretic effect and promote excretion.

5. One trillion trees could reverse climate change

gossip

The global initiative of "planting 1 trillion trees" has recently gained more and more support. If so many trees can be planted, it will be no problem to absorb global carbon emissions and reverse climate change.

▲“One Trillion Tree Declaration” (Photo source: Plant-for-the-planet.org)

the truth

"One trillion" is a very large number. Planting so many trees requires about 900 million hectares of land, which is close to the entire land area of ​​China. Trees play a very important role in the ecosystem. In addition to conserving water, reducing soil erosion and improving air quality, they can also absorb carbon dioxide through photosynthesis. Statistics show that my country has planted about 66 billion trees in the past 40 years. Satellite data shows that China is the main contributor to the greening of the world. Studies have shown that China's forest area has increased significantly, and forest carbon absorption has reached 45% of China's emissions.

Previous studies have had significant discrepancies in their estimates of the amount of carbon dioxide absorbed by trees each year. For example, the European Environment Agency estimates that a tree absorbs 22 kilograms of carbon dioxide each year in its first 20 years of growth. Other organizations estimate that the average tree in the world absorbs about 10 kilograms of carbon dioxide each year. According to the latter estimate, 1 trillion trees absorb about 10 billion tons of carbon dioxide each year.

According to current policies of various countries, global carbon dioxide emissions will reach 55 billion tons by 2030. Even if the goal of planting 1 trillion trees can be achieved, the new trees can only absorb about 1/5 of carbon emissions (10 billion tons), which is still a long way from absorbing all greenhouse gases emitted by humans.

Humanity hopes to plant another 1 trillion trees through efforts, which will face many practical challenges. However, the academic community still generally supports planting trees because restoring forests can absorb a large amount of greenhouse gases and play an important role in protecting the ecology and restoring biodiversity.

6. Inhaling hydrogen can fight tumors, fight aging, and cure all diseases

gossip

Inhaling hydrogen can prevent and treat various diseases, even cancer, and it can also resist aging.

(Photo source: Modern Express)

the truth

According to the promotion of some "hydrogen inhalation health centers", whether it is anti-tumor, anti-aging, or improving sleep and other difficult and complicated diseases, it seems that all problems can be solved as long as you inhale a breath of hydrogen.

In fact, although hydrogen has "antioxidant" properties under laboratory conditions, showing the effects of reducing inflammatory responses and inhibiting tumor growth, relevant clinical research is still in progress. Whether in terms of scientific principles or actual medical applications, there are still many questions and doubts about the mechanism of action of hydrogen that have not been solved.

Hydrogen cannot reach the lesions in a targeted manner through "inhaling hydrogen" or drinking "hydrogen-rich water". Even if there are some breakthroughs or progress in the laboratory or clinic, the use of hydrogen to treat or prevent diseases is still a medical act and needs to be used in hospitals or medical institutions under the advice of a qualified doctor, rather than in small shops on the street or at home.

In short, don’t believe rumors that “hydrogen inhalation” can cure all diseases, and don’t easily try “hydrogen inhalation” or drink “hydrogen-rich water”.

7. Honey does not affect blood sugar, so diabetics can eat it without worry

gossip

Honey is a natural food, most of which is fructose, which has a low glycemic index. Therefore, eating honey will not increase blood sugar in diabetics, so they can eat it with confidence.

(Photo source: Visual China)

the truth

Fructose does have a low glycemic index, but its content in honey is not absolutely dominant. Honey still contains a lot of glucose, which has a great impact on blood sugar. According to the quality requirements for honey in "GB 14963-2011 National Food Safety Standard Honey", the total content of fructose and glucose in every 100g of honey should be ≥60g. Therefore, honey itself is a food with a very high sugar content and is not suitable for diabetic patients to consume in large quantities.

Moreover, fructose can easily lead to obesity and insulin resistance, which is the basis for the onset of type 2 diabetes. In addition, high fructose intake is also an important risk factor for hyperuricemia and gout. Therefore, not only diabetic patients, but also gout patients and hyperuricemia patients should try to avoid eating too much food containing a lot of fructose.

8. Soaking in hot water or sitting by a fire can cure frostbite

gossip

It is important to rewarm after frostbite, and the fastest way to do this is to soak in hot water or sit by a fire.

(Photo source: Visual China)

the truth

After frostbite, many patients will use some "home remedies" to treat themselves, such as rubbing with snow, roasting with fire, rewarming with hot water, etc. However, many methods are not medically valid. After the frostbitten area is stimulated, it may lead to irritation allergies and infection risks, resulting in large lumps and blisters on the frostbitten area.

Frostbite refers to systemic or local acute frostbite damage caused by exposure of the body to a low temperature environment, which is more common in cold areas. The correct way to deal with frostbite is to put the frozen part into warm water close to human body temperature, such as using 37℃-40℃ warm water or a warm towel to rewarm for 5-10 minutes (no more than 20 minutes). If conditions permit, rinse it with sterile warm saline. The affected limb should be braked and appropriately raised to avoid aggravating tissue damage and reduce edema.

In the cold winter season, you should protect the exposed parts of your skin. When you go out, you should wear masks, gloves, windproof earmuffs, etc. You should always keep your clothes, shoes and socks dry. If you find signs of frostbite, you can first use some frostbite cream to promote local blood circulation. If the frostbite is serious and symptoms such as blisters appear, the best way is to go to the hospital for treatment as soon as possible.

9. Turning the gas stove valve to the right may cause explosion

gossip

When the valve of the gas stove is turned to the right, the small fire will cause gas leakage from the outer circle, which may easily cause an explosion.

(Photo source: Beijing Evening News)

the truth

Will this use method cause the danger of gas leakage? In this regard, the reporter asked five stove manufacturers, including Fotile, Vatti, Robam, Midea, and Beijing Gas Stove, and the answer was no.

The staff of Fotile gas stoves told reporters that this statement on the Internet is unscientific. Most of Fotile's stoves have the lowest fire when the valve is turned to 180 degrees, that is, at the 6 o'clock position, and only the innermost circle has a small fire. When the valve is turned back clockwise, close to the position where the fire is about to be turned off, which is equivalent to an angle of 30 degrees, the inner and outer circles will simultaneously become small fires. At this time, both the inner and outer circles have fires. The stove is designed with this fire adjustment gear, so it can be used normally without worry. There is no problem of gas leakage when it is adjusted to this gear.

The staff of Midea gas stove also said that when adjusting the low fire, 90 degrees is used as the benchmark. Usually, turning left means that the inner ring keeps the maximum fire, and the outer ring fire gradually decreases until the outer ring fire goes out and the inner ring fire is reduced to the minimum fire. Turning right means that the inner and outer ring fires decrease at the same time until the gas is turned off. Both ways of adjusting the low fire are correct and can be adjusted according to cooking needs.

It should be noted that if the gas stove does not have a flameout protection function, do not adjust the flame too small when turning it to the right to adjust the flame to a low level. Pay attention to whether the valve is turned back to the closed position at 12 o'clock when the flame goes out, so as to avoid gas leakage due to flame extinction.

10. Gray hair can reduce the risk of cancer

gossip

A new study from Harvard University shows that having gray hair is not all bad - it can reduce your risk of cancer.

(Photo source: Visual China)

the truth

The study introduced in the online article was published in 2009, which is 12 years ago. It is not a new study, but an experiment conducted by Japanese researchers on mice. The original study explored the mechanism of hair graying, and the study did not contain relevant data on cancer incidence.

The online article claiming that "growing gray hair can reduce the risk of cancer" was quoted from a foreign media report. The report misinterpreted the opinions of experts and came to such an absurd conclusion. In the report, David Fisher, director of the Department of Dermatology at Harvard University, was quoted as interpreting the study. Professor Fisher believes that if melanocyte stem cells that have suffered DNA damage do not transform into melanocytes and still exist in the state of stem cells, although they can produce melanin, they will become cancerous and cause cancer. Transforming into mature melanocytes reduces the risk of cancer.

Therefore, when we say "cancer risk is reduced", we are comparing the effects of "melanin stem cells continuing to survive as stem cells" and "transforming into melanocytes" on the human body, rather than comparing the cancer risks of "people with black hair" and "people with gray hair". If people with gray hair really have a lower risk of cancer as the online article says, doesn't that mean that the elderly are less likely to get cancer? That is obviously absurd and contradicts the fact that "the older you are, the higher the risk of cancer."

(Sources of this issue: Beijing Science and Technology Daily, Beijing Daily WeChat account, "China Meteorological" WeChat public account, Beijing Youth Daily, Tencent Jiuzhen, Science and Technology Daily, Beijing Evening News)

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