The Bush administration finally concluded what we’ve been suspecting for some time now: that the climate is changing, and that human-generated increases in greenhouse gas concentrations are “very likely” to be the cause of global warming.

The “Scientific Assessment of the Effects of Global Change on the United States” has been released on Thursday after four long years of waiting and a court order to give it a little push. The report (.pdf) acknowledges the climate change that is already being felt in the United States.

The findings are based on previous reports, including those of the U.N. Intergovernmental Panel on Climate Change, and were released two days before the actual deadline, May 31. The administration was forced to come up with the report after environmental groups took the matter to court.

The report concluded that in the last 50 years, heat wave occurrences increased in the U.S., the sea-level constantly reflected a rise every year, while the number of Atlantic hurricanes also increased.

Human activities contributed to climate extremes, such as abnormal temperatures; less frequent, but more intense precipitations; larger peak wind speeds.

Carbon dioxide levels have altered not only patterns of precipitations, and consequently U.S. water resources, agriculture, land resources and biodiversity, but also human health. The report added that the trend is very likely to continue over the next few decades.

Among the conclusions of the report, due to an increased frequency and severity of heat waves, the population is likely to be more exposed to illnesses and death, especially the young, elderly, frail and poor.

At the same time, increases in extreme weather (storms, flooding) and accompanying events (wildfires following long periods of drought) may also increase death rate, as well as increase the number of injuries, infectious diseases, interruption of medical care for chronic disease treatment, and stress-related disorders, and series of diverse social effects, as disruption and migration.

According to the Global Change Research Act (1990), the government needs to issue a report on global warming every four years. However, no other report has been issued since 2000, which determined environmental groups to demand the Bush administration to fulfill its obligations.

It is well known that the Bush administration takes more of an economic approach on global warming, rather than an objective one, and that greenhouse emissions regulation is not something they support.