The proportion of Americans who say that the earth is getting warmer has decreased modestly since January 2007, mostly because of a decline among Republicans. Republicans are increasingly skeptical that there is solid evidence that the earth has been warming over the past few decades: just 49% of Republicans say there is evidence that the earth’s average temperature has been rising, down 13 points since January 2007.
Overall, 71% of Americans say there is solid evidence of higher global temperatures, compared with 77% at the beginning of last year. There is less of a consensus about the cause of global warming. Roughly half of Americans (47%) say the earth is warming because of human activity, such as the burning of fossil fuels.
But nearly as many people (45%) say that rising global temperatures are either mostly caused by natural environmental patterns (18%), say they do not know the cause of warming (6%), or say that no solid evidence of warming exists (21%).
The latest national survey by the Pew Research Center for the People & the Press, conducted April 23-27 among 1,502 adults, finds that the already substantial partisan divide over global warming has widened in the past year. Fully 84% of Democrats and 75% of independents say there is evidence that the earth’s temperatures have been rising, compared with just 49% of Republicans.
Among Republicans, far more moderates and liberals than conservatives say there is evidence of global warming (69% vs. 43%). However, the proportion of both groups expressing this view has declined since January 2007.
What Causes Global Warming
Currently, 47% of Americans say that the earth is getting warmer and that this is occurring because of human activity, such as the burning of fossil fuels. Opinions about the primary cause of global warming have remained stable in recent years.
Nearly six-in-ten Democrats (58%) and half of independents (50%) say global warming is mostly caused by human activity; only about quarter of Republicans (27%) express this view.
There also are age differences in opinions about the cause of global warming. More than half of people under age 30 (54%) believe that the earth is warming mostly because of human activity compared with only 37% of those ages 65 and older.
In addition, college graduates are more likely than those with a high school education or less to say that human activity is causing global warming (51% college graduate vs. 43% high school or less).
Comparable proportions of Democrats who are college graduates (88%) and those with less education (82%) say that there is solid evidence that the earth is getting warmer. Among Democrats, higher education is associated with the belief that global warming is mostly caused by human activity. Fully 75% of Democrats with college degrees say that the earth is warming and that this is caused by human activity. Just 52% of Democrats with less education express this view.
Among Republicans, similar percentages of college graduates and those with less education say there is solid evidence of global warming (46% and 51%, respectively). Yet for Republicans, unlike Democrats, higher education is associated with greater skepticism that human activity is causing global warming. Only 19% of Republican college graduates say that there is solid evidence that the earth is warming and it is caused by human activity, while 31% of Republicans with less education say the same.
Reducing the Effects of Global Warming
Despite the huge partisan differences over whether the earth is warming, majorities of those in both parties who say there is evidence of global warming believe that it is possible to reduce the effects of higher global temperatures.
Overall, 74% of those who say there is solid evidence of global warming say it is possible to reduce its effects, up from 67% in June 2006. Among those who believe there is solid evidence that the earth is getting warmer, there is little difference in those who think that it is possible to reduce the effects among Republicans (69%), Democrats (74%), and independents (77%).
About half of the public (47%) says that people will have to make major sacrifices to reduce the effects of global warming. Only about half as many (23%) says that technology can solve global warming without requiring major sacrifices. More Democrats and independents (49% each) than Republicans (38%) say that major sacrifices will be needed to reduce global warming.
An overwhelming majority of those who believe that global warming is caused by human activity (82%) say it is possible to reduce its effects, and 54% say that major sacrifices are needed. By comparison, 57% of those who say global warming is caused by natural patterns in the earth’s environment believe it is possible to reduce its effects, and just 32% say people will have to make major sacrifices to accomplish this goal.
A Serious Problem
Most Americans believe that global warming is a serious problem. Fully 73% say it is a very or somewhat serious problem, while 24% say it is not too serious (13%) or not a problem (11%), which is largely unchanged from recent years.
Nearly six-in-ten Democrats (57%) and 46% of independents say that global warming is a very serious problem; this compares with just 22% of Republicans. As many Republicans say that global warming is not a problem (23%) as say it is a very serious problem (22%). And just 18% of conservative Republicans say that global warming is a very serious problem, compared with 27% who say it is not a problem. By contrast, 35% of moderate and liberal Republicans say it is a very serious problem while 11% say it is not a problem.
People’s evaluations of the seriousness of global warming are strongly linked to views about whether human activity is the cause of higher temperatures. About seven-in-ten (69%) of those who believe that human activity is the cause of warming say that this is a very serious problem, compared with 33% of those who say warming is caused by natural patterns, and 7% who do not believe the earth is warming.
Global Warming Lags as a Policy Priority
Although most Americans say that global warming is a very or somewhat serious problem, it ranked at the bottom of the public’s list of policy priorities for the president and Congress this year. In January 2008, only 35% of Americans said it should be a top priority for the president and Congress this year, down slightly from a year earlier (38%).
The issue of global warming rates as a relatively low priority for both Democrats and independents, and is by far the lowest-rated priority for Republicans among 21 issues. More than three times as many Democrats (47%) and independents (38%) than Republicans (12%) rated global warming as top priority. This issue has dropped in importance among Republicans since 2007 when 23% rated global warming as a top priority. Ratings among Democrats and independents have remained relatively stable over this period. (“An Even More Partisan Agenda for 2008,” Jan. 24.)
View the topline questionnaire at pewresearch.org/pewresearch-org/politics
