Americans Believe 2015 Was Record-Warm, but Split on Why

PRINCETON, N.J. -- U.S. government scientists recently reported that 2015 was the Earth's warmest year since reliable record keeping began. Majorities of U.S. adults surveyed in Gallup's annual Environment poll are aware of this finding and believe it is accurate, but they are almost evenly divided on whether the record-high temperatures are attributable mainly to human-caused climate change (49%) or natural variability (46%).

	Yes%	No%	No opinion%
Heard reports that 2015 was Earth's warmest year on record	63	37	*
Believe reports are accurate	69	27	4
* Less than 0.5%
Gallup, March 2-6, 2016

	Main cause%
Human-caused climate change	49
Natural changes in the Earth's temperatures	46
Other/No opinion	5
Gallup, March 2-6, 2016

Majority of Americans Aware of Reports of Record Temperatures for 2015

When asked if they had heard that scientists recently reported that 2015 was the Earth's warmest year on record, 63% of U.S. adults said they had. This awareness varies somewhat among key demographic sectors -- particularly education, age and race.

College graduates are substantially more likely than those with no college to have heard of the reports, 76% vs. 53%. A large gap is also evident by age: 70% of those aged 55 and older are familiar with the reports, compared with 53% of 18- to 34-year-olds. Whites (68%) are more likely than nonwhites (52%) to have heard. Partisan differences are insignificant, with 66% of Democrats and 64% of Republicans hearing about the reports of record temperatures in 2015.

	Yes, had heard%	No, had not heard%
U.S. adults	63	37
18 to 34	53	47
35 to 54	63	37
55+	70	29
White	68	32
Nonwhite	52	47
College graduate	76	24
Some college	62	38
No college	53	46
Republican	64	36
Independent	62	37
Democrat	66	34
Gallup, March 2-6, 2016

Majority Also Believe the Reports Are Accurate

All adults were next asked whether they believe the reports are accurate. A somewhat larger majority than had heard of the reports say they are accurate, 69%, while 27% say they are not. Compared with the question about awareness of the reports, the patterns by subgroup change substantially on the question of their accuracy.

While Republicans and Democrats are similarly aware of the reports about 2015's record warmth, there are striking partisan differences in terms of belief in the reports' accuracy: 84% of Democrats believe them, compared with 52% of Republicans.

Young adults (aged 18 to 34) are more likely to believe the reports than their older (55 and older) counterparts, 78% vs. 65%. There is a modest difference between whites (67%) and nonwhites (74%) in the perceived accuracy of the reports. College graduates are also modestly more likely to believe the reports than those with no college, 75% vs. 67%.

	Accurate%	Not accurate%	No opinion%
U.S. adults	69	27	4
18 to 34	78	20	2
35 to 54	68	29	4
55+	65	31	4
White	67	29	3
Nonwhite	74	23	3
College graduate	75	22	2
Some college	66	29	5
No college	67	29	3
Republican	52	45	3
Independent	70	26	4
Democrat	84	12	3
Heard of 2015 climate reports	76	23	1
Had not heard of reports	58	35	7
Gallup, March 2-6, 2016

Americans Split on Primary Cause of Record Warmth

A third question in the March 2-6 poll asked adults if, assuming the reports are true, they think the record 2015 global temperatures are mainly attributable to human-caused climate change or to natural changes in the Earth's temperatures. Here, the U.S. public is sharply divided. Forty-nine percent attribute the record temperatures to human-caused climate change, while 46% attribute them to natural changes.

Not surprisingly, given the degree to which climate change has become a highly polarized political issue, there is a chasm between Republicans and Democrats on the source of 2015's record-high global temperatures. While 72% of Democrats attribute the record temperatures to human-caused climate change, only 27% of Republicans do so. This mirrors the continued large partisan gap in views of global warming documented in other items in this year's Environment poll.

Younger adults (those 18 to 34) are also much more likely than older Americans (55 and older) to attribute the record warmth to human-caused climate change, 61% vs. 39%. There are also noticeable differences by education and race: College graduates are more likely than those with no college to choose human causation (56% vs. 42%), and nonwhites are more likely than whites to do so (58% vs. 46%).

	Climate change%	Natural changes%	Reports are not accurate (vol.)%	No opinion%
U.S. adults	49	46	2	3
18 to 34	61	38	1	*
35 to 54	52	45	2	1
55+	39	54	2	5
White	46	51	2	2
Nonwhite	58	37	2	4
College graduate	56	40	1	3
Some college	52	44	2	2
No college	42	53	2	3
Republican	27	72	1	1
Independent	47	48	3	2
Democrat	72	24	1	2
Heard of 2015 climate reports	53	43	2	2
Had not heard of reports	43	52	2	4
Reports are accurate	62	35	1	2
Reports are not accurate	20	74	3	3
(vol.) = Volunteered response; * Less than 0.5%
Gallup, March 2-6, 2016

As Gallup reported previously, the same poll found 63% of Americans saying that temperatures where they live have been warmer than usual this winter and 10% saying they were colder than usual. About half of each group -- or 38% of all Americans -- attribute the unusual winter weather to climate change caused by human activity. That is somewhat less than the percentage attributing last year's record warmth at the global level to human-caused climate change.

Bottom Line

A strong majority of Americans, including 52% of Republicans, accept that 2015 was a record-setting warm year. However, they are sharply divided, especially on the basis of political affiliation, on the sources of the record temperatures. This is yet another indication of the extreme degree of partisan polarization surrounding climate change that has evolved in the U.S. over the past decade.

Riley E. Dunlap is Gallup Scholar for the Environment and Regents Professor of Sociology at Oklahoma State University.

Survey Methods

Results for this Gallup poll are based on telephone interviews conducted March 2-6, 2016, with a random sample of 1,019 adults, aged 18 and older, living in all 50 U.S. states and the District of Columbia. For results based on the total sample of national adults, the margin of sampling error is ±4 percentage points at the 95% confidence level. All reported margins of sampling error include computed design effects for weighting.

Each sample of national adults includes a minimum quota of 60% cellphone respondents and 40% landline respondents, with additional minimum quotas by time zone within region. Landline and cellular telephone numbers are selected using random-digit-dial methods.

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