Persistent efforts to combat air pollution and conserve water and forests have helped Beijing stage a green Winter Olympics, an environment official said on Tuesday.

"In today's Beijing, blue skies dotted with white clouds have become the norm," Yu Jianhua, deputy head of the Beijing Municipal Ecology and Environment Bureau, told a news conference at the 2022 Beijing Media Center.

Beijing's air quality last year was the best in historical records, he said. The average concentration of fine particulate matter less than 2.5 micrometers in diameter was 33 micrograms per cubic meter, which met the national air quality standard.

The Chinese capital saw 288 days with good air quality last year, accounting for about 79 percent of the year.

The amount of water stored in the Miyun Reservoir, in the city's Miyun district, reached a record 3.5 billion cubic meters, and forests covered nearly half the city's land area, he said.

"We aim to create an environment where people can see scenery when they open the window and see greenery when going out," Yu said. "Since Beijing bid for the Olympics, the city has insisted on green development and hosting the Games in a green way."

Decades of efforts had contributed to great improvement, he said.

To reduce carbon emissions, the capital focused on low-carbon development in the energy, construction and transportation sectors. Last year, the carbon intensity for every 10,000 yuan ($1,574) worth of GDP was about 0.41 metric tons, down 28 percent compared with 2015, Yu said.

By the end of 2017, the city's plain areas were basically "free of coal".Additionally, the capital saw the number of new energy vehicles owned by residents rise to 506,000, Yu said.

The city also carried out multiple rounds of analysis of PM2.5 sources, with monitoring systems covering both air and land.

Joint prevention and control of air pollution was conducted by authorities in Beijing, Tianjin, Hebei province and surrounding areas, Yu said.

"The areas adopted scientific and technological pollution control and held consultations to share information about air quality forecasts," he said. "We have been inheriting good environmental protection experiences and creating new ones."

For example, in the economic field, the capital has introduced environmental protection and water resource taxes. It also built a green financial system and a carbon emission trading system, Yu said.