Global mean temperature is a combination of observation stations all over the world daily measurement of sea surface temperature and the ship measured in all the different waters of sea surface temperature, estimates arrived at. Instrument observations over the past 157 years shows that the Earth's surface temperatures worldwide have increased by, but there are significant regional differences. The global average, over the past 100 years (1906 ~ 2005) of warming occurred in two periods, the 20th century, 10 years to 40 years and 70 years since the 20th century, and then a phase of greater warming. Over the past 25 years, the warming rate has accelerated, and the 12 warmest years have occurred in just 11 years in the past 12 years.Usually much higher than land-based warming oceans, especially in the 20th century, since the 70's has been particularly evident. There are heat island effect in urban areas due to warming. At the same time, since the late 20th century, 50 years of global observations show that tropospheric temperatures, and higher rate of slightly larger than the surface, while the stratosphere since 1979, the temperature decreased. Since 1901, has been cooling a few areas, especially in the south of Greenland near the northern North Atlantic. Warming during this period the most inland areas are in Asia and North America north.Recently, people have begun analysis of the world's extreme temperatures in many parts of Japan's long-term changes, including North America and parts of southern South America, Europe, Asia, north and east, southern Africa and Oceania. Especially from the 20th century, 50 years since the observational record shows that a very cold day and night records were reduced, while the extreme heat during the day and warm night, the record has increased. The majority of the two hemispheres, the high latitudes, frost-free period was longer. In the northern hemisphere, mainly for the early arrival of spring.It is also the use of sounding balloons and satellites on the ground above the air temperature observations. For the 20th century, global observations since the 50's, all the latest information on available sequences show that the tropospheric warming slightly larger than the surface, while the stratospheric cooling since 1979, clearly show that increasing concentrations of greenhouse gases can be so that the troposphere warming, stratosphere cooling Er Shi, ozone depletion cools the stratosphere also have a major impact.With the observations of surface temperature rise is consistent, rivers and lakes freeze period shortened. At the same time, the 20th century, the quality and extent of glaciers in almost all over the world reduced; the recent melting of Greenland ice sheet is already very obvious; Arctic sea ice thickness and extent in all seasons radiate downward trend, especially for spring and summer; sea level due to thermal expansion of sea and land ice melting and rising.