How Fast is The Earth Heating Up?

Much debate in the last five years about the greenhouse effect has centered on interpreting temperature numbers generated at weather stations all over the world. The data from these thermometers are averaged and plotted in attempts to determine just how fast the earth has heated up since the measurements began. There is now no doubt the world is getting warmer. The thermometers show that the world is warmer now than at any time since the measurements started. The year 1990 was the hottest year in the last century. Together with 1991, the years of 1983, 1987, 1988, and 1989, have been measured to be the warmest 6 years in the last hundred years. 1991 was the second warmest year of the past century, perhaps due to the eruption of Mt. Pinatubo during that year. The ash from the volcano in the upper atmosphere blocks some sunlight to earth, and is expected to generate a temporary two or three year cooling effect. After that time, most ash particles will have settled back to earth, and most scientists expect to see the global warming trend continue.

According to scientists, we can with "99% confidence conclude that current temperatures represent a real warming trend rather than a chance fluctuation over the 30-year period." Most scientists agree that the planet's temperature has risen 0.5 degrees Celsius since 1900, and will continue to increase at an increasing rate. The environment is responding to this warming. For instance, a study of mountain plants in the Alps (Europe), shows that some cold-loving plants are starting to move to higher and cooler altitudes. That is a possible response to increasing temperatures.