Editor's note: "Natural Facts – Q&A" is a special series that answers questions on natural conditions involving winter sports. In this episode, China Meteorological Administration sheds light on the importance of weather conditions for curling.

Even for an indoor sport like curling, the weather still matters. In fact, curling has strict requirements for temperature and humidity. Weather conditions, such as rain and snow, and even the presence of spectators at the venue can affect temperature and humidity levels inside the venue, thereby influencing the coefficient of friction between the stone and ice and thus affecting performance. What more is there to be considered? Let's hear it from China Meteorological Administration.

Q: How should the ice rink be for curling?

A: According to international competition standards, the temperature of the ice rink must be controlled between -4 to -6 degrees Celsius and the air humidity should be maintained at 35 percent to ensure the proper smoothness, hardness and viscosity of the rink. 

Q: Do curling events have stricter requirements for illumination?

A: Generally speaking, the lighting level of the venue should rise above 1,000 Luxes, to ensure brightness while not harming the athletes' eyes. The illumination of a living room is 100 Luxes, and the office desk is about 500 to 600 luxes. 

(Cover image designed by CGTN's Feng Yuan)

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