DOI: 10.3886/e234241v1
title: Climate.gov Data Snapshots: Temperature - Global Monthly, Difference from Average, Additional Resolutions

description: <b>This file contains additional resolutions of the same images as in
https://www.datalumos.org/datalumos/project/233461/version/V2/view.</b>
<br>

<b><br></b><b>Q: Where was the
monthly temperature warmer or cooler than usual? </b>




<b><br></b><b>A: </b>Colors
show where average monthly temperature was above or below its
1991-2020 average. Blue areas experienced cooler-than-usual
temperatures while areas shown in red were warmer than usual. The
darker the color, the larger the difference from the long-term
average temperature. 




<b><br></b><b>Q: Where do these
measurements come from? </b>




<b><br></b><b>A: </b>Weather
stations on every continent record temperatures over land, and ocean
surface temperatures come from measurements made by ships and buoys.
NOAA scientists merge the readings from land and ocean into a single
dataset. To calculate difference-from-average temperatures—also
called temperature anomalies—scientists calculate the average
monthly temperature across hundreds of small regions, and then
subtract each region’s 1991-2020 average for the same month. If the
result is a positive number, the region was warmer than the long-term
average. A negative result from the subtraction means the region was
cooler than usual. To generate the source images, visualizers apply a
mathematical filter to the results to produce a map that has smooth
color transitions and no gaps. 




<b><br></b><b>Q: What do the
colors mean?</b>



<b><br></b><b>A:</b> Shades of
red show where average monthly temperature was warmer than the
1991-2020 average for the same month. Shades of blue show where the
monthly average was cooler than the long-term average. The darker the
color, the larger the difference from average temperature. White and
very light areas were close to their long-term average temperature.
Gray areas near the North and South Poles show where no data are
available. 




<b><br></b><b>Q: Why do these
data matter?</b>



<b><br></b><b>A:</b> Over time,
these data give us a planet-wide picture of how climate varies over
months and years and changes over decades. Each month, some areas are
cooler than the long-term average and some areas are warmer. Though
we don’t see an increase in temperature at every location every
month, the long-term trend shows a growing portion of Earth’s
surface is warmer than it was during the base period. 




<b><br></b><b>Q: How did you
produce these snapshots?</b>



<b><br></b><b>A:</b> Data
Snapshots are derivatives of existing data products: to meet the
needs of a broad audience, we present the source data in a simplified
visual style. NOAA's Environmental Visualization Laboratory (NNVL)
produces the source images for the Difference from Average
Temperature – Monthly maps. To produce our images, we run a set of
scripts that access the source images, re-project them into desired
projections at various sizes, and output them with a custom color
bar. 

Additional
information
Source images
available through NOAA's Environmental Visualization Lab (NNVL) are
interpolated from data originally provided by the National Center for
Environmental Information (NCEI) - Weather and Climate. NNVL images
are based on NOAA Merged Land Ocean Global Surface Temperature
Analysis data (NOAAGlobalTemp,
formerly known as MLOST). 




<b><br></b><b>References</b> <br>
NCEI
Monthly Global Analysis <br>NOAA
View Temperature Anomaly <br>Merged
Land Ocean Global Surface Temperature Analysis <br>Global
Surface Temperature Anomalies <br>Climate
at a Glance - Data Information 




<br>Source:
https://www.climate.gov/maps-data/data-snapshots/data-source/temperature-global-monthly-difference-a...




<br>
This upload
includes two additional files:<br>
* Temperature - Global Monthly,
Difference from Average _NOAA Climate.gov.pdf is a screenshot of the
main Climate.gov site for these snapshots
(https://www.climate.gov/maps-data/data-snapshots/data-source/temperature-global-monthly-difference-a...)<br>
*
Cimate_gov_ Data Snapshots.pdf is a screenshot of the data download
page for the full-resolution files. <br>
description: Data is divided in to folders by image resolution -- kml (zip), small
(png), and broadcast (png). Occasionally there may be one image
missing in a particular size but available in another size.<br>
<br>
Data
downloaded from climate.gov on 6/22/2025. <br>


 
 
 
 


This file contains additional resolutions of the same images as in
https://www.datalumos.org/datalumos/project/233461/version/V2/view.<br>