The greenhouse effect: a global threat.

From a physical phenomenon, the greenhouse effect has led to a terrible consequence, causing adverse climate change on Earth, awakening anxiety in all of humanity and every nation across different continents.

Global concern

Therefore, this year's Climate Change Summit, held over the past few days in New York (USA), was more well-attended than ever before, with the presence of high-ranking government leaders from 120 countries and representatives from 200 multinational corporations and companies.

UN Secretary-General Ban Ki-moon speaks at the UN Climate Change Summit in New York. Photo: Reuters.

And the situation became more heated than ever in many major cities around the world, from New York (USA) to Paris (France), from London (UK) to Sydney (Australia), etc., with over 2,000 massive protests involving 600,000 people. Even UN Secretary-General Ban Ki-Moon took to the streets. People directed their attention, first and foremost, to the leading politicians of nations and the top executives of international corporations. They must take responsibility and act to prevent humanity from facing the threat of the "greenhouse effect," of climate change; which, according to Ban Ki-Moon, is a "flaw of our time." And according to the UN Secretary-General, every person living on this Earth also has a responsibility for the increase in greenhouse gas emissions and for contributing to the worsening of the "greenhouse effect."

By now, perhaps everyone should have a clearer understanding of the concept of the greenhouse effect, its dangers, and thus see the necessity of contributing to stopping the increase in greenhouse gas emissions.

The dangers of the "greenhouse"

The concept of the greenhouse effect is best understood in the specific case of a completely enclosed house, with all four sides and the roof made of transparent glass. A good example is a flower greenhouse in the cool climate of Da Lat. Here, because sunlight penetrates the glass walls and roof, the heat from the sun is absorbed by the air inside the house, warming the entire space, not just the areas directly illuminated. This heat is then trapped inside for a long time. This phenomenon of heat absorption and retention is precisely what we call the greenhouse effect.

This concept can be extended to the Earth today, where our planet's atmosphere is surrounded by a special layer of gases. For this "home" of Earth, in terms of heat transfer, the "glass" is made up of carbon dioxide (CO2) molecules and other gases, also emitted by humans: CO2, CFCs, CH4, O3, NO2… and water vapor; listed in decreasing order of their greenhouse effect.

This special "glass layer" does not prevent sunlight (primarily short-wave radiation or ultraviolet rays) from penetrating and reaching the Earth's surface, but it does prevent reflected light (primarily long-wave radiation or infrared rays) from escaping into the atmosphere after some of the sunlight is absorbed by the Earth and the rest is reflected back into space.

Illustrate the role of the greenhouse effect in influencing the Earth's surface temperature.

Thus, CO2 and the aforementioned greenhouse gases retain the sun's heat, preventing it from reflecting back into space. If greenhouse gases exist at moderate concentrations, they help keep the Earth's temperature from becoming too cold, but if concentrations are as high as they are now, the consequence is that the atmosphere and the Earth's surface will heat up. In reality, the current concentration of carbon dioxide (CO2) is around 0.036%, causing the Earth's temperature to rise by approximately 30°C. However, without these greenhouse gases, the temperature would drop to around -15°C.

Clearly, it is the greenhouse gases emitted by humans, through the greenhouse effect, that have caused the Earth's temperature to rise to the point where global climate change is increasingly negatively impacting human life. At this rate of increase, the danger will eventually threaten the lives of hundreds of millions of people, if not the very survival of humanity.

Currently, the impacts of climate change are manifesting in many ways.

For example, impacts on water resources lead to shortages of drinking water, water for agriculture (for irrigation, aquaculture, etc.), for industry (supplying hydroelectric power, etc.), and for forestry (forest fires, etc.).

For ecosystems, global warming alters the normal living conditions of organisms (many species have their habitats reduced or are wiped out...) and threatens human health (human health deteriorates, many new diseases emerge, epidemics spread...).

In particular, at some point, if the Earth's temperature rises high enough, it could rapidly melt the ice and snow in the Arctic and Antarctic, causing sea levels to rise too high, potentially leading to catastrophic floods. For example, in the United States, sea levels are predicted to rise by 50 cm by 2100, potentially eliminating 5,000 square miles of dry land and 4,000 square miles of wetlands.

Let's work together to save the Earth.

The atmosphere inside and outside this year's Climate Change Summit in New York demonstrated that the Earth is truly entering a critical period with the increase in greenhouse gas emissions, primarily carbon dioxide (CO2). And it is time for all nations and all people to take action and work together to save the Earth.

Speaking at the 2014 New York Conference, the UN Secretary-General issued a call to action: "To weather this storm, we need the cooperation of all countries. We have never faced a challenge like this before." He reiterated the previous goal of keeping global temperatures from rising by more than 2 degrees Celsius, emphasizing its importance as a key element of climate change action programs.

Through declarations, policies, or concrete actions, most nations have demonstrated their readiness to join the effort to save the Earth—that is, to save their own country, to save humanity—that is, to save their own people, themselves, and future generations.

At the New York Summit last September, governments agreed on principles to expand the use of renewable energy, nuclear power, and increase support for developing countries in their efforts to slow global warming.

In fact, some countries, such as the Nordic countries, Germany, Spain, etc., have shifted their investment towards wind and solar power, despite the high costs. Countries like France, the US, and South Korea maintain or add new nuclear power plants. Many countries, such as India, Poland, China, and newly developed countries in the Middle East, Southeast Asia, and even Africa, have chosen the path of developing nuclear power and gradually reducing coal-fired power.

Nuclear power plants – the "nemesis" of the global climate change threat. Photo: Source www.ecofriend.org.

On the other hand, national leaders have also set targets to prevent the damage caused by deforestation, increase food production, and boost the use of electric vehicles in cities by 30% by 2030.

Not only governments, but also businesses are committed to investing in a "low-carbon" economy. Total investment from countries and businesses amounts to $200 billion between now and 2015. Some cities, which contribute up to 70% of greenhouse gas emissions, such as New York, Paris, Johannesburg, Seoul, and many other major cities, have already made pledges to reduce CO2 emissions.

Clearly, the New York Summit in September 2014 sent out encouraging signals for the cause of saving the Earth from the dangers of climate change.

However, many concerns remain. Many major countries, crucial in the fight against climate change, did not send their highest-ranking representatives to the Conference. In particular, the Conference concluded without an international agreement capable of defining specific criteria, concrete steps, and assigning responsibilities to each country, etc.

However, it should also be understood that this is merely a preparatory summit aimed at creating further political momentum and advancing the negotiation process within the framework of the UNFCCC Framework Convention on Climate Change, in preparation for the upcoming summit in Lima later this year.

And everyone hoped that meaningful legal agreements would be reached at the subsequent UNFCCC Conference of States, in Paris, in 2015.

According to Vietnamnet