NASA researchers have estimated that the force of the volcanic eruption that took place on Saturday near the island nation of Tonga was equivalent to 10 megatons of TNT, which means it was more than 500 times as powerful as the nuclear bomb the United States dropped on Hiroshima, Japan.

Three of Tonga's smaller islands suffered serious damage from tsunami waves up to 15 meters high and according to United Nations humanitarian officials about 84,000 people, more than 80 percent of Tonga's population, have been impacted by the volcano's eruption. On Wednesday, the prime minister declared a state of emergency.

In a message to King of Tonga Tupou VI the same day, President Xi Jinping said he was shocked to learn of the natural disaster. Extending sincere sympathies to the Tongan government and people on behalf of the Chinese government and people, and in his own name, he promised that China will do its best to help. That help is already materializing. On Monday, the Red Cross Society of China provided $100,000 in emergency assistance to Tonga. On Tuesday, the Ministry of Foreign Affairs said that China had prepared disaster-relief materials such as drinking water, food, personal protective equipment, as well as rescue devices, and the materials will be arriving now that Tonga's airport is operational again.

The UN Office for the Coordination of Humanitarian Affairs, citing Tongan authorities, has said that the most pressing humanitarian needs are safe water, food and non-food items, and the top priorities are reestablishing communication services including the internet.

China and Tonga are comprehensive strategic partners, and Xi said that China stands ready to provide as much support as possible to help the Tongan people prevail over the disaster.

Besides China, the international community has been rallying to provide assistance to Tonga, proving once again that when it comes to natural disasters, at least, there are no barriers of race, language or ideology. There is only unity and the joining of hands.

Volcanic eruptions are only one type of natural disaster, of course, and climate change is increasing the frequency and severity of others. The rising temperatures are driving up sea levels, worsening the impacts of tsunamis and storm surges on low-lying islands and coastal areas.

China is doing its best to help developing countries build capacity against climate change through various forms of results-oriented South-South cooperation, and this cooperation has yielded tangible results. But more concerted efforts are needed to curb the rise in global temperatures, as the world's actions so far fall well short of what is needed.

As Xi said in his speech at the Leaders Summit on Climate in April last year, "When people pull together, nothing is too heavy to be lifted". Although climate change is a pressing, formidable and long-term challenge, it can be overcome with the same kind of solidarity and mutual assistance being demonstrated in the helping hands reaching out to assist the people of Tonga in their time of need.