text: Climate Sibu has a tropical rainforest climate according to the Köppen climate classification. The Sibu town has high temperatures of  and low temperatures of . Annual rainfall is approximately , with relative humidity between 80 and 87%. Sibu receives between 4 and 5 hours of sunlight per day with yearly average daily values of global solar radiation of 15.2 MJ/m2. Cloud cover over Sibu reduces during the months of June and July (6.75 Oktas) but increases from November to February (7 Oktas).
  Demographics
  The change in Sibu's population since 1947 is shown below:
  Ethnicity
  According to the 2010 Malaysian census, the town of Sibu (excluding suburban area) has total population of 162,676. Chinese (52.1%, 82,019) is the largest ethnic group in the town, followed by indigenous people (35.01%, 56,949), non-Malaysians (1.99%, 3,236), and Indians (0.37%, 598). Among the indigenous tribes, there are Iban (28,777), Malays (24,646), Melanau (16,028), Bidayuh (3,337), and other indigenous tribes (1874). A majority of the non-Malaysians are Indonesian workers employed at plywood and sawmills factories. There are also a number of illegal workers employed by syndicates to tap rubber. A number of foreign Chinese nationals and Indonesians are also working in massage parlours.
  Languages
  Since the majority of the town population is made up of Fuzhounese, Hokkien and Hakka Chinese, Mandarin Chinese being the lingua franca of all three dialect groups and usage of dialects such as the Fuzhou dialect, Hakka and Hokkien are commonly spoken amongst the Chinese community. The majority of Sibu Chinese are multilingual and are able to speak both Sarawak Malay and English. Indigenous languages such as Sarawak Malay, Melanau, Bidayuh and Iban are also spoken.