How are global temperatures changing?

1. Since 1861, the global average surface temperature has fluctuated and increased. The two periods with the largest increases in the 20th century were 1910-1945 and 1976-2000. 1998 was the warmest year. 2. Reason: The massive emission of greenhouse gases hinders the normal heat dissipation of the earth. Hazards: ① The global land precipitation has changed significantly. Precipitation in the mid-to-high latitudes of the Northern Hemisphere has increased by an average of 0.5%-2% every 10 years, in the tropics by an average of 0.2%-0.3% every 10 years, and in subtropical regions with an average decrease of about 0.3% every 10 years. ②Snow cover and glacier area decrease. Satellite data shows that global snow cover has decreased by about 10% since the late 1960s. Ground observations show that alpine glaciers in areas other than the Arctic and Antarctic have generally retreated in the 20th century. ③Global average sea level rises. Tide data show that global sea level rose by 0.1-0.2 meters in the 20th century. The average sea level along the coast of mainland my country has also shown a clear upward trend. In the past 100 years, it has risen by approximately 0.14 meters. ④Global climate change itself is a change in resource conditions. For example, the increase or decrease in temperature and precipitation means changes in heat resources and water resources, and changes the spatial distribution pattern of water and heat resources, making it more difficult for humans to develop and utilize natural resources in many areas. ⑤Global climate change intensifies natural disasters. For example, in the second half of the 20th century, the frequency of heavy rains in mid- and high latitudes increased by 2%-4%, while in some areas of Asia and Africa, the frequency and intensity of metal decadal droughts increased. ⑥Global climate change will also lead to changes in the original ecosystem. According to relevant research, if the trend of global climate warming is not effectively curbed, one-third of the world's animal and plant habitats will have undergone fundamental changes by 2100, which will make it difficult for a large number of species to adapt to the new environment. extinct due to the environment. ⑦Global climate change has a more significant impact on major production areas, such as agriculture, forestry, animal husbandry, fishery and other sectors. As far as agriculture is concerned, climate change will have a certain impact on agricultural output, crop varieties, farming methods, and the stability of agricultural production. ⑧Climate change will expand the prevalence of certain diseases through extreme weather and climate events (El Niño, drought, floods, heat waves, etc.), causing harm to human health.