The average temperature in the contiguous United States reached 55.5 degrees Fahrenheit (13 degrees Celsius) in 2024, approximately 3.5 degrees Fahrenheit higher than the 20th-century average. These levels represented a record since measurements started in ****. Monthly average temperatures in the U.S. were also indicative of this trend. Temperatures and emissions are on the rise The rise in temperatures since 1975 is similar to the increase in carbon dioxide emissions in the U.S. Although CO₂ emissions in recent years were lower than when they peaked in 2007, they were still generally higher than levels recorded before 1990. Carbon dioxide is a greenhouse gas and is the main driver of climate change. Extreme weather Scientists worldwide have found links between the rise in temperatures and changing weather patterns. Extreme weather in the U.S. has resulted in natural disasters such as hurricanes and extreme heat waves becoming more likely. Economic damage caused by extreme temperatures in the U.S. has amounted to hundreds of billions of U.S. dollars over the past few decades.

The North America climate data were derived from WorldClim, a set of global climate layers developed by the Museum of Vertebrate Zoology at the University of California, Berkeley, USA, in collaboration with The International Center for Tropical Agriculture and Rainforest CRC with support from NatureServe.The global climate data layers were generated through interpolation of average monthly climate data from weather stations across North America. The result is a 30-arc-second-resolution (1-Km) grid of mean temperature values. The North American data were clipped from the global data and reprojected to the standard Lambert Azimuthal Equal Area projection used for the North American Environmental Atlas. Background information on the WorldClim database is available in: Very High-Resolution Interpolated Climate Surfaces for Global Land Areas; Hijmans, R.J., S.E. Cameron, J.L. Parra, P.G. Jones and A. Jarvis; International Journal of Climatology 25: 1965-1978; 2005.Files Download

The North American Dataset contains sets of Maximum, Minimum and Average Temperature data and Precipitation data that are either (1) raw (non-adjusted though flagged for possible quality issues), (2) adjusted due to time of observation bias (TOB) or (3) put through the Pairwise Homogenization Algorithm (PHA). These files contain North American stations and its data are measured in hundredths of degrees Celsius (without decimal place) for temperature and tenths of millimeters (without decimal place) for Precipitation. Each file includes the entire available Period of Record.

The monthly average temperature in the United States between 2020 and 2025 shows distinct seasonal variation, following similar patterns. For instance, in April 2025, the average temperature across the North American country stood at 12.02 degrees Celsius. Rising temperatures Globally, 2016, 2019, 2021 and 2024 were some of the warmest years ever recorded since 1880. Overall, there has been a dramatic increase in the annual temperature since 1895. Within the U.S. annual temperatures show a great deal of variation depending on region. For instance, Florida tends to record the highest maximum temperatures across the North American country, while Wyoming recorded the lowest minimum average temperature in recent years. Carbon dioxide emissions Carbon dioxide is a known driver of climate change, which impacts average temperatures. Global historical carbon dioxide emissions from fossil fuels have been on the rise since the industrial revolution. In recent years, carbon dioxide emissions from fossil fuel combustion and industrial processes reached over 37 billion metric tons. Among all countries globally, China was the largest emitter of carbon dioxide in 2023.

The North America climate data were derived from WorldClim, a set of global climate layers developed by the Museum of Vertebrate Zoology at the University of California, Berkeley, USA, in collaboration with The International Center for Tropical Agriculture and Rainforest CRC with support from NatureServe.The global climate data layers were generated through interpolation of average monthly climate data from weather stations across North America. The result is a 30-arc-second-resolution (1-Km) grid of mean temperature values. The North American data were clipped from the global data and reprojected to the standard Lambert Azimuthal Equal Area projection used for the North American Environmental Atlas. Background information on the WorldClim database is available in: Very High-Resolution Interpolated Climate Surfaces for Global Land Areas; Hijmans, R.J., S.E. Cameron, J.L. Parra, P.G. Jones and A. Jarvis; International Journal of Climatology 25: 1965-1978; 2005.Files Download

This dataset provides values for TEMPERATURE reported in several countries. The data includes current values, previous releases, historical highs and record lows, release frequency, reported unit and currency.

This metadata record describes the 30-year annual average of precipitation in millimeters (mm) and temperature (Celsius) during the period 1990–2019 for North America. The source data were produced by and acquired from DAYMET daily climate data (2020) and presented here as a series of two 1-kilometer resolution GeoTIFF files. An open source python code file used to process the data is also included.

The North America climate data were derived from WorldClim, a set of global climate layers developed by the Museum of Vertebrate Zoology at the University of California, Berkeley, USA, in collaboration with The International Center for Tropical Agriculture and Rainforest CRC with support from NatureServe.The global climate data layers were generated through interpolation of average monthly climate data from weather stations across North America. The result is a 30-arc-second-resolution (1-Km) grid of mean temperature values. The North American data were clipped from the global data and reprojected to a Lambert Azimuthal Equal Area projection. Background information on the WorldClim database is available in: Very High-Resolution Interpolated Climate Surfaces for Global Land Areas; Hijmans, R.J., S.E. Cameron, J.L. Parra, P.G. Jones and A. Jarvis; International Journal of Climatology 25: 1965-1978; 2005.Files Download

The mean annual temperature in North America stood at -4.5 degrees Celsius in 1995. It is expected that, 30 years later in 2025, the average temperature will increase by 1.6 degrees Celsius due to the effects of global warming, under a scenario where global temperatures increase by 1.5 degree Celsius.

The Daily Air Temperature and Heat Index data available on CDC WONDER are county-level daily average air temperatures and heat index measures spanning the years 1979-2010. Temperature data are available in Fahrenheit or Celsius scales. Reported measures are the average temperature, number of observations, and range for the daily maximum and minimum air temperatures, and also percent coverage for the daily maximum heat index. Data are available by place (combined 48 contiguous states, region, division, state, county), time (year, month, day) and specified maximum and minimum air temperature, and heat index value. The data are derived from the North America Land Data Assimilation System (NLDAS) through NLDAS Phase 2, a collaboration project among several groups: the National Oceanic and Atmospheric Administration (NOAA) National Centers for Environmental Prediction (NCEP) Environmental Modeling Center (EMC), the National Aeronautics and Space Administration (NASA) Goddard Space Flight Center (GSFC), Princeton University, the National Weather Service (NWS) Office of Hydrological Development (OHD), the University of Washington, and the NCEP Climate Prediction Center (CPC). In a study funded by the NASA Applied Sciences Program/Public Health Program, scientists at NASA Marshall Space Flight Center/ Universities Space Research Association developed the analysis to produce the data available on CDC WONDER.

Western North American Temperature Atlas

https://doi.org/10.5061/dryad.70rxwdc4v

0.5° spatial field reconstruction of summer (June-August) average maximum temperatures for western North America, spanning 1553-2020 CE and based on tree ring density and blue intensity measurements.

Description of the data and file structure

The data consists of 3029 grid point reconstructions of summer average maximum temperatures. In the Excel file, rows 1 and 2 are the Latitude/Longitude coordinates for each reconstruction. Rows 3-470 are the annual reconstruction estimates. Estimates are displayed as z-scores, relative to the period 1553-2020 CE.

This map shows the projected average change in mean temperature (°C) for 2081-2100, with respect to the reference period of 1986-2005 for RCP2.6. The median projected change across the ensemble of CMIP5 climate models is shown.

For more maps on projected change, please visit the Canadian Climate Data and Scenarios (CCDS) site: http://ccds-dscc.ec.gc.ca/index.php?page=download-cmip5.

The map shows the mean January daily temperature based on the 30-year period 1941-1970. The lowest mean January daily temperatures are below -35 degrees Celsius and are located on Ellesmere Island and on Axel Heiberg Island and south of the Boothia Peninsula in Nunavut. The highest mean January daily temperatures are above 0 degrees Celsius and are located on the west coast of British Columbia. Generally, the mean increases from north to south, from -35 to -2.5 degrees Celsius. In Canada temperature regimes change drastically from season to season, and even within a season there are often marked changes which affect the whole nature and character of outside activities. The major factors that affect temperature are latitude and thus the length of daylight; elevation; distribution of land and water; and prevailing winds and storm tracks. Although the least direct and the least intense incoming solar radiation occurs in December, there is a lag in the cooling of the Earth’s surface. As a result, the coldest month in Canada is normally January. All temperature reporting stations in Canada are equipped with self-registering maximum and minimum thermometers, which are mounted in standard louvred instrument shelters. Ideally, the shelters are located a little more than a metre above the ground in open spaces that are considered to be representative of the area. The thermometers are read once or several times each day to obtain daily maximum and minimum temperature values. Daily values of maximum and minimum temperature are collected every month from approximately 2000 stations across Canada. From these data, various statistics, such as monthly means, are calculated. The mean daily maximum temperature for any month is the mean of all daily maximum temperatures recorded in that particular month for the period of record. The mean daily minimum temperature is calculated similarly. The mean daily temperature for the month is the average of the mean daily maximum and mean daily minimum values. For obvious socio-economic reasons, the climatological stations used in the analysis are not uniformly located across Canada. The majority are situated in populated areas along the southern fringe of the country. In the mountainous regions of western Canada, most of the stations are located in accessible valleys, and the pattern of the maps is generally indicative of valley conditions only. No attempt was made to allow for detailed topographic effects, as such a pattern would be too complicated to display on the scale used.

Temperatures have risen in the last 100 years around the world. In the 1910s, North America had an average temperature some **** degrees Celsius lower than average temperatures between 1910 and 2000. In the most recent decade, this region experienced temperatures **** degrees Celsius over the average. All global regions (excluding Oceania) experienced an increased temperature over one degree Celsius in the 2010s, compared to the average between 1910 and 2000.

Daily maximum and minimum air temperature data were obtained from the Global Historical Climatology Network daily (GHCNd, Menne, et al. 2012) and the Great Lakes Air Temperature/Degree Day Climatology, 1897-1983 (Assel et al. 1995). Daily air temperature was calculated by taking a simple average of daily maximum and minimum air temperature. To accurately capture climate trends and variability, it is critical to ensure data consistency across the historical record, such as spatial coverage, a number of representative weather stations, and measurement details (e.g., sensor types and heights, measurement protocols) as any inconsistencies could result in apparent climate change in the data record. Bearing this in consideration and following Cohn et al. (2021), a total of 24 coastal locations along the Great Lakes were selected (see Figure 1 in the Method Document). These 24 locations had relatively consistent station data records since the 1890s while data from other locations had large gaps in time, or had inconsistencies among data from neighboring stations. Each of the selected locations had multiple weather stations in their proximity covering the historical period from 1890s to 2023, representing the weather conditions around the _location. Only a couple of stations covered the whole historical period (e.g., Green Bay, WI). Therefore, for most of the locations, datasets from multiple stations in the proximity of each _location were combined to create a continuous data record from the 1890s to 2023 (see Table 1 in the Method Document for station information and periods for which the station data was used). When doing so, data consistency was verified by comparing the data during the period when station datasets overlap. This procedure resulted in almost continuous timeseries, except for a few locations that still had temporal gaps of one to several days (e.g., Escanaba, MI). Therefore, any temporal data gap less than 10 days in the combined timeseries were filled based on the linear interpolation. This resulted in completely continuous timeseries for all the locations. Average daily air temperature was calculated from January 1, 1897 to October 22, 2023 by simply making an average of timeseries data from corresponding locations around each lake. This resulted in daily air temperature records for all five Great Lakes (Lake Superior, Lake Huron, Lake Michigan, Lake Erie, and Lake Ontario). The cumulative freezing degree days (CFDDs) and the net melting degree days (NMDDs) were also added to this version of the dataset. The description of the calculation methods for CFDD and NMDD can be found in the method document included in this dataset.

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This map shows the projected average change in mean temperature (°C) for 2081-2100, with respect to the reference period of 1986-2005 for RCP8.5. The median projected change across the ensemble of CMIP5 climate models is shown.

For more maps on projected change, please visit the Canadian Climate Data and Scenarios (CCDS) site: http://ccds-dscc.ec.gc.ca/index.php?page=download-cmip5.

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Average Annual Temperature (2015-2030) simulated by RegCM3 with GENMOM projections as boundary conditions.

Units are degrees Celsius.

These data were generated by the regional climate model RegCM3 with boundary conditions from a GCM future climate projections. The data were downscaled statistically by calculating differences (anomalies) between the RegCM3 results with GCM-driven boundary conditions for 1968-99 and those for a future period, in this case 2015-2030. The anomalies were added (temperatures) or multiplied (precipitation) to a climate baseline from PRISM (Parameter-elevation Regressions on Indepenent Slopes Model - prism.oregonstate.edu) data based on historical observations. The PRISM baseline was calculated as average monthly climate conditions for 1968-1999 reprojected the results to the BLM Albers 4km grid. PRISM data are provided in a 2.5 arc-minute lat-lon grid.

RegCM3 is the third generation of the Regional Climate Model originally developed at the National Center for Atmospheric Research during the late 1980s and early 1990s. Details on current model components and applications of the model can be found in numerous publications (e.g., Giorgi et al, 2004a,b, Pal et al, 2007), the ICTP RegCNET web site (http:users.ictp.itRegCNETmodel.html), and the ICTP RegCM publications web site (http:users.ictp.it~pubregcmRegCM3pubs.htm). The Western North America domain has a horizontal grid spacing of 15 km and 18 vertical levels.

RegCM3 requires time-dependent lateral (wind, temperature, and humidity) and surface [surface pressure and sea surface temperature (SST)] boundary conditions that are updated every 6 hours of simulation. Lateral boundary conditions are derived from General Circulation Model (GCM) output or observations (e.g. NCEP). Additional information can be found at: http:regclim.coas.oregonstate.edu.

GENMOM is a recently developed GCM that includes components that have been applied extensively to climate research. The model is relatively low resolution (T31, ~3.75o x 3.75o) by design, a compromise that allows long simulations in reasonable time so that the model can be applied to paleoclimate experiments that commonly are run for multiple decades and centuries. GENMOM simulations of future climate were produced under the A2 emission scenario as part of a larger data-model comparison effort to test the ability of GCMs and RCMs to simulate North American climate and climatic variability in response to changes in global boundary conditions (e.g, insolation, atmospheric composition, continental ice sheets, sea level and paleogeography). Details and an evaluation of the model to simulate present-day climatology are given in Alder et al (2011).

This map shows the projected average change in mean temperature (°C) for 2016-2035, with respect to the reference period of 1986-2005 for RCP2.6. The median projected change across the ensemble of CMIP5 climate models is shown. For more maps on projected change, please visit the Canadian Climate Data and Scenarios (CCDS) site: http://ccds-dscc.ec.gc.ca/index.php?page=download-cmip5.