Snow and freezing rain in China were disrupting travel on Monday and had already caused hundreds of rail and flight cancellations, as millions of people traveled across the country before lunar new year holiday begins this weekend. For many years, heavy travel within and into China ahead of the holiday, known as Spring Festival in Chinese, produced the world’s largest annual migration. During the coronavirus pandemic, fear of lockdowns, quarantines and other rules deterred many from traveling. Last year, the authorities abruptly lifted those rules weeks before lunar new year…