Coinciding with the release of the January 2023 Global Climate Report, the NOAA Global Surface Temperature (NOAAGlobalTemp) dataset version 5.1.0 replaced version 5.0.0. This new version includes complete global coverage and an extension of the data record back in time an additional 30 years to January 1850. While anomalies and ranks might differ slightly from what was reported previously, the main conclusions regarding global climate change are very similar to the previous version. Please see our Commonly Asked Questions Document and web story for additional information.
NOAA's National Centers for Environmental Information calculates the global temperature anomaly every month based on preliminary data generated from authoritative datasets of temperature observations from around the globe. The major dataset, NOAAGlobalTemp version 5.1.0, updated in 2023, uses comprehensive data collections of increased global area coverage over both land and ocean surfaces. NOAAGlobalTempv5.1.0 is a reconstructed dataset, meaning that the entire period of record is recalculated each month with new data. Based on those new calculations, the new historical data can bring about updates to previously reported values. These factors, together, mean that calculations from the past may be superseded by the most recent data and can affect the numbers reported in the monthly climate reports. The most current reconstruction analysis is always considered the most representative and precise of the climate system, and it is publicly available through Climate at a Glance.
April 2023 was the fourth-warmest April for the globe in NOAA's 174-year record. The April global surface temperature was 1.00°C (1.80°F) above the 20th-century average of 13.7°C (56.7°F). The 10 warmest April months have occurred since 2010. April 2023 marked the 49th consecutive April and the 530th consecutive month with global temperatures, at least nominally, above the 20th-century average.
Global ocean temperatures set a record high for April at 0.86°C (1.55°F) above the long-term average. This marked the second-highest monthly ocean temperature for any month on record, just 0.01°C (0.02°F) shy of the record-warm ocean temperatures set in January 2016. On April 13, NOAA's Climate Prediction Center announced an El Niño Watch alert status, as ENSO-neutral conditions are expected to last through the Northern Hemisphere spring with a 62% chance of El Niño developing May–July 2023.
Yearly time series of sea surface temperature, globally averaged between [60°S-60°N]. Dashed black lines are the 2-standard deviation for the climatological mean (black line). Note: data are preliminary.
Multiple international sea surface temperature (SST) products depicted rapid ocean warming at the beginning of 2023 after the long-lived La Niña began to wane. A few products, including NOAA's 1/4° Daily Optimum Interpolation Sea Surface Temperature (OISST), indicated record SST warmth at the end of March and early April, although SST started decreasing to below 21°C by late April. Short term SST fluctuation is normal, and it is important to keep in mind all data have noise which could lessen the degree to which the temperature anomaly is seen as extreme. In the case of early 2023, all major global SST products showed rapid ocean surface warming, but not all showed the warming as record breaking. It still remains to be seen whether the warmth will continue through the next few months, or whether an El Niño event will develop.
The Southern Hemisphere experienced its warmest April and warmest month on record. The April 2023 temperature surpassed that of the previous record-warm month in the Southern Hemisphere, March 2016, by 0.06°C (0.10°F). April 2023 marked the first month in the Southern Hemisphere where average temperatures exceeded 0.90°C above the 20th-century average. Meanwhile, the Northern Hemisphere had its ninth-warmest April, although ocean-only temperatures in the Northern Hemisphere tied with 2020 as warmest on record for the month.
Temperatures were above average throughout most of northeastern North America and Greenland, parts of Central and South America, Africa and Antarctica. In addition, above-average temperatures covered parts of western Europe, eastern and western Asia and Oceania. Sea surface temperatures were above average across much of the northern, western and southwestern Pacific, the central and southern Atlantic and the Indian Ocean. Record warm temperatures covered just over 5% of the world's surface in April.
Temperatures were near to cooler than average across parts of western North America and Alaska, central and eastern Europe, India, central China, central Russia and western Australia. Sea surface temperatures were near to below average over parts of the southeastern and eastern Pacific and the northern Atlantic Ocean. Less than 1% of the world's surface had a record-cold April.
A smoothed map of blended land and sea surface temperature anomalies is also available.
Africa had its fourth-warmest April on record, while South America tied 2007 for its ninth-warmest April.
- Argentina recorded an April temperature that was 0.4°C above average, making it the 14th-warmest April on record for the country.
Asia had an above-average April temperature (22nd warmest), but it was the smallest April temperature anomaly since 2010.
- Thailand recorded its second-warmest April on record.
- Hong Kong recorded a monthly temperature 0.6°C above average, and precipitation was about half of its normal April amount.
- In Pakistan, the national mean temperature for April was 0.26°C below the average.
North America, Europe and Oceania had an above-average April temperature, but did not rank among the top 20 warmest Aprils on record.
- Spain had its warmest and driest April on record.
- Latvia recorded its fifth-warmest April on record since 1924.
- The city of Reykjavik, Iceland had its seventh-warmest April on record.
- The provisional mean temperature for April in the United Kingdom was 7.8°C, which is 0.1°C below average.
- In Switzerland, April temperature was 1.0°C below the 1991–2020 average.
- The Netherlands recorded an April temperature that was 1.1°C below the norm.
- New Zealand had its 11th-warmest April on record.
(out of 174 years)
|Land and Ocean||+1.00||+1.80||Warmest||4th||2016||+1.14||+2.05|
|Land and Ocean||+1.08||+1.94||Warmest||9th||2016||+1.45||+2.61|
|Land and Ocean||+0.93||+1.67||Warmest||1st||2023||+0.93||+1.67|
|Land and Ocean||+0.93||+1.67||Warmest||7th||1989||+1.45||+2.61|
|Land and Ocean||+1.62||+2.92||Warmest||22nd||2020||+3.58||+6.44|
500 mb maps
In the atmosphere, 500-millibar height pressure anomalies correlate well with temperatures at the Earth's surface. The average position of the upper-level ridges of high pressure and troughs of low pressure—depicted by positive and negative 500-millibar height anomalies on the map—is generally reflected by areas of positive and negative temperature anomalies at the surface, respectively.
Year-to-date Temperature: January–April 2023
The January–April global surface temperature also ranked fourth warmest in the 174-year record at 1.03°C (1.85°F) above the 1901–2000 average of 12.6°C (54.8°F). According to NCEI's statistical analysis, the year 2023 is very likely to rank among the 10 warmest years on record.
January to April was characterized by warmer-than-average conditions across much of northern and eastern North America, South America, Europe, Africa, Asia, and the Arctic, as well as across parts of Antarctica and northern and southwestern Oceania. Sea surface temperatures were warmer than average across much of the northern, western, and southwestern Pacific, the central and southern Atlantic, and parts of the Indian Ocean.
Meanwhile, near- to cooler-than-average conditions were present across parts of central-western North America, southeastern Greenland and Iceland, north-central Australia, Antarctica, and northeastern Asia. The central, eastern tropical and southeastern Pacific experienced near- to cooler-than-average sea surface temperatures during this year-to-date period.
A smoothed map of blended land and sea surface temperature anomalies is also available.
Europe and Africa each had their third-warmest year-to-date. South America had its seventh-warmest January–April period, while Asia had its ninth-warmest such period. January–April ranked 15th-warmest in North America and tied 1992 for 23rd-warmest in Oceania. Overall, the Northern Hemisphere had its fourth-warmest year-to-date, while the Southern Hemisphere had its fifth-warmest such period.
(out of 174 years)
|Land and Ocean||+1.03||+1.85||Warmest||4th||2016||+1.26||+2.27|
|Land and Ocean||+1.34||+2.41||Warmest||4th||2016||+1.70||+3.06|
|Land and Ocean||+0.72||+1.30||Warmest||5th||2016||+0.82||+1.48|
|Land and Ocean||+0.18||+0.32||Warmest||43rd||1968||+0.69||+1.24|
|Land and Ocean||+2.42||+4.36||Warmest||9th||2016||+4.12||+7.42|
The maps shown below represent precipitation percent of normal (left, using a base period of 1961–1990) and precipitation percentiles (right, using the period of record) based on the GHCN dataset of land surface stations.
Above-average April precipitation was observed across parts of the eastern and southeastern U.S., northern South America, Italy, central-east Africa, the Arabian peninsula, central and eastern China and eastern Russia. Drier-than-average conditions were present across much of the western and central U.S., southern South America, western Europe (except Italy), northern Africa, eastern Oceania and Southeast Asia.
Global Precipitation Climatology Project (GPCP)
The following analysis is based upon the Global Precipitation Climatology Project (GPCP) Interim Climate Data Record. It is provided courtesy of the GPCP Principal Investigator team at the University of Maryland.
- Niño sea surface temperatures (SSTs) have become positive, and precipitation anomaly features have transitioned to more neutral-like conditions across the tropics.
- Over western North America, the end of La Niña SST conditions in the Pacific oddly resulted in now drier conditions in California and surrounding areas, which is usually associated with La Niña.
- Flooding with heavy rains occurred in parts of central-east Africa; meanwhile, drought was severe in Spain and northern Africa, e.g., Tunisia.
- A very distinct rainfall positive anomaly at the Ecuador-Peru coast was associated with large positive SSTs just offshore.
April continues our annual seasonal transition with global precipitation patterns moving northward, but with an added transition related to the shift from La Niña to neutral ENSO conditions in the tropical Pacific. As part of the overall typical seasonal pattern (Fig. 1, top panel) the tropical eastern Pacific Ocean shows the usual double ITCZ with two bands just north and south of the Equator. This feature was also evident last month, and is typical of the season. The other climatological features of low latitudes (broad ITCZ across land and ocean areas, sub-tropical minima) are evident. Further poleward, the contrasting mid-latitude features of the northern and southern hemispheres are seen, with southwest-northeast orientations of precipitation features broken up by the continents in the Northern Hemisphere, and a near continuous east-west precipitation feature at a higher latitude in the Southern Hemisphere. All of these features set the stage for examining the deviations from climatological values (as seen in Fig. 1, middle and bottom panels).
Besides the seasonal transition, another transition from the recent multi-year La Niña conditions that have dominated the precipitation anomaly patterns of those years to the neutral ENSO index SST conditions is playing an important role this month. The Niño 3.4 ENSO index for April has moved to positive territory (+ 0.9) from negative La Niña values a few months earlier. But, as noted last month, the precipitation patterns often lag the SST situation by a month or two. Figure 2 shows the anomaly patterns for the April La Niña composite and this April's anomaly pattern repeated from Fig. 1. In the central tropical Pacific the two patterns roughly match, with negative anomalies dominating, indicating that the La Niña effect is still important there. However, elsewhere the pattern match is weak or missing. The ENSO transition over the last few months is captured in the first three rows of Table 1 by the pattern correlation numbers as a function of time for the monthly anomaly patterns vs. the month-of-the-year composites for different ENSO conditions. For December 2022 through February 2023, the correlations are positive for La Niña and negative for El Niño, indicating the strong La Niña pattern then and which extended back two years. But, in March, and now for this April, the La Niña correlation is only weakly positive. This pattern correlation change is connected to the positive trend in the Niño 3.4 ENSO index during the five months shown. The lag effect can be seen in the table as while the Niño 3.4 index moves toward neutral during the months shown, the La Niña pattern correlation only starts being affected in March and April. We will continue to track these pattern correlations as we progress further into ENSO neutral conditions and possibly a later El Niño.
Table 1. Spatial correlations between monthly precipitation anomalies (P) during the last five months and corresponding ENSO composites for El Niño, La Niña, and neutral conditions between 40°N–40°S. Monthly Niño 3.4 and Niño 1+2 Index values are also included.
For April, all of the ENSO pattern correlations are near zero (Table 1), seemingly indicating mostly non-ENSO effects on this month's patterns. Over the Maritime Continent and Australia areas of dry conditions are mixed with above average rains east of the Philippines and in north-central Australia, where Cyclone Ilsa came ashore along the northwest coast and tracked to the south. In South Asia, a positive rain anomaly is evident over the Indian sub-continent, associated with dryness in Indochina and very heavy rain and flooding in central and eastern China. Although the Horn of Africa was still dry in April, further south in eastern Africa, rainfall was well above average and led to flooding and landslides in Burundi and the eastern part of the Democratic Republic of Congo. In the Middle East, positive anomalies also dominate with significant rainfall even on the Arabian peninsula, with flooding noted in Iraq and Iran and further to the northwest in Ukraine.
Western Europe has been suffering from a long general drought, but Italy this month has areas of high rainfall with even floods in some of the southern provinces. But to the west, the precipitation deficits persist, especially on the Iberian peninsula where Spain endured a heat wave and an intensification of the drought there. This dry situation was also evident across the Mediterranean into northern Africa, especially in Tunisia
In the Americas, a mottled pattern of precipitation anomalies is evident, with South America showing a north-south pattern of alternating surpluses and deficits compared to climatological precipitation. Northern South America had rainfall surpluses with an interesting significant positive anomaly at its west coast just south of the Equator. This anomaly feature was embedded in that southern branch of the double ITCZ over the ocean, and as that southern branch extends into Ecuador and Peru. This heavy rainfall feature was associated with a very large SST positive anomaly right just off the coast that appeared as a first indicator of the transition from La Niña. In Table 1 (last row) that SST anomaly is indicated as the Niño 1+2 index, which has gone from negative to very large positive the last two months, clearly related to the rainfall excesses in the region
In North America over the past year, La Niña has not had the usual effect, but rather the opposite effect. The heavy rains and snow of the last few months up to recently have largely eliminated the California drought and provided an enormous snowpack in the Sierra Nevada Mountains and an above-average snowfall in the Rocky Mountains, especially in southwest Colorado. Now that La Niña has waned, the anomaly pattern has more the look of a La Niña pattern with mostly precipitation deficits in the western U.S. However, large runoff from the melting snowpacks may lead to flooding in California despite last month's precipitation deficits. Further east, a mild drought in much of the northeast U.S. brought even a large, brief wildfire in New Jersey, with some relief for the area in the last weeks of the month. Over the southeast U.S., above-normal rainfall was present near the coast, with even a singular type of event with a 20-inch rainfall event in one day in Fort Lauderdale, FL thas was associated with localized flooding.
Drought in April 2023
- Beneficial precipitation fell across parts of the drought areas in all of the continents during April 2023, but in many cases the precipitation wasn't enough to erase months of deficits, and the precipitation missed other parts of the drought areas.
- The month was drier than normal over parts of the drought-plagued agricultural lands of North America, Europe, Africa, South America, and southern China.
- A significant amount of the world's agricultural lands was still suffering from low soil moisture and groundwater levels, with agriculture most threatened in parts of the Americas, Africa and southern parts of Europe.
Southern and northern portions of Europe were drier than normal during April, while central to eastern portions were near to wetter than normal. In the south, the dry area was centered on the Iberian Peninsula, which was also unusually warm. According to the State Meteorological Agency (AEMET), Spain had its warmest and driest April on record. In the north, April was drier than normal in the Baltic Rim region. The last 2 to 3 months have been excessively dry along the Mediterranean coast of Europe from Spain to Italy, with warmer-than-normal temperatures increasing evapotranspiration as seen in the Evaporative Stress Index (ESI). Dryness extends from this region north to Poland and other Baltic states at longer time periods, according to the 12- to 72-month Standardized Precipitation Index (SPI). Unusually warm conditions in recent years across Europe increased evapotranspiration, magnifying drought as seen in the 9- to 48-month Standardized Precipitation Evapotranspiration Index (SPEI). The last 12 months (May 2022–April 2023) ranked as the second warmest such period continent-wide in the 1910–2023 NCEI record. Satellite-based (GRACE) indicators of groundwater and soil moisture revealed the impacts of this persistent dryness across much of the continent with low groundwater and soil moisture levels evident.
The European Combined Drought Indicator showed some level of drought across the Mediterranean coast from Iberia to Italy, in Scandinavia and the Baltics, and over portions of the Balkans, with 21.6% of the EU-27 territory in Drought Warning conditions and 3.2% in Drought Alert conditions. According to media reports (FreshFruitPortal.com), the unusually warm, dry winter in Southern Europe has led to dry conditions that have delayed planting due to reduced water availability for agricultural activities. Delayed planting is also expected to affect yield for fruits and vegetables in the region. The AP and Reuters reported that drought in northeastern Spain could lead to a "drought emergency" by September as reservoirs drop to just more than a quarter of capacity—reservoirs were at 50% of capacity countrywide, except in the northeast where levels were nearer to 25%. Many of Catalonia's rivers are flowing at record low rates. Reuters added that, in Spain, about 80,000 people in Alcaracejos and another 27 villages in the province of Cordoba depend on water being delivered by trucks as one reservoir was empty and the water from another nearby reservoir was not safe for consumption. The AP reported that extreme drought in Spain's agricultural heartlands has led to a request for emergency funds from the European Union. The drought "emergency" or "alert" classification covers 27% of the country. Euronews noted that water storage in parts of Italy is less than half of normal, which could jeopardize agricultural production. Precipitation was below normal during the winter, setting up the country for a second year of drought. The AP reported that, by the end of April, the largest river in Italy, the Po, has already become as low as it was last summer as winter snow fields, that usually keep it from drying up in the warmer months, have receded by 75%, per the Bolzano climate and environment agency. The Connexion reported that French President Emmanuel Macron has been called on to "prevent a human catastrophe" in the parched Pyrenees-Orientales department in southern France. The area has not received substantial rain in more than a year. The drought and high wildfire risk could lead to a human catastrophe this summer. The BBC added that bans on car-washing, garden-watering and pool-filling will begin in France on May 10. CPH Post noted that farmers in Denmark were struggling to grow crops due to the drought.
Asia had a patchwork of divergent precipitation anomalies during April. The month was drier than normal over northwestern, southwestern, southeastern, and northeastern Arctic regions, with wet conditions in between these regions. Monthly temperatures were warmer than normal in the east and west and near to cooler than normal in between. The warm temperatures increased evapotranspiration, as seen in the ESI. The SPI showed dryness in the southwestern, southeastern, and northeastern areas at the 2- to 6-month time scales. Parts of central to northwest Asia were dry at 9 to 12 months, while Southwest Asia was persistently dry at all time scales out to the last 6 years. The last 12 months ranked as the fourth warmest May–April period, continent-wide, according to NCEI data. The anomalously warm temperatures of the last several years increased evapotranspiration, exacerbating drought conditions as seen in the SPEI. GRACE satellite observations revealed low groundwater and soil moisture across much of China to Mongolia, Southwest Asia, Southeast Asia, and northwest Asia.
Beneficial precipitation fell across parts of East Africa in April, while parts of central and southern Africa and the Mediterranean coast (the Maghreb region) continued drier than normal. Most of these areas were also warmer than normal. The April (and March) precipitation helped alleviate some of the East African dryness in the short-term, but drier-than-normal conditions were still evident in the Horn of Africa at the 6-month and longer time scales, especially as monitored by the SPEI. Warmer-than-normal temperatures enhanced evapotranspiration in April, especially in the Maghreb region, as seen on the ESI. Africa had the fourth warmest April and sixth warmest May–April, continent-wide, in the NCEI record. The dryness in the Maghreb region extended across a large part of northwest Africa at the 1-month to 6-year time scales. It was associated with a dry weather pattern over the western Mediterranean that affected this part of Africa as well as adjacent parts of southwestern Europe and was most noticeable in the SPEI. Satellite (GRACE) observations revealed improved soil moisture in parts of East Africa, but low groundwater and soil moisture persist across North Africa, other parts of East Africa, and central to southern parts of the continent. An analysis by the African Flood and Drought Monitor estimated 20% of the continent in drought at the end of April. According to media reports (AP), the severe lack of precipitation affecting the Maghreb has lowered water storage at almost all of the 30-plus dams in Tunisia, with water storage some dams as low 17%. This has prompted Tunisian authorities to shut off water nightly from 9 p.m. to 4 a.m. in an effort to conserve water. Reuters noted that (in spite of the recent rains) more than four million people in the Horn of Africa were still in desperate need of humanitarian aid.
Most of Australia was near to wetter than normal during April 2023, except for some drier-than-normal areas in the west and northeast. The SPI and SPEI revealed dryness in eastern Australia at the 3- to 6-month time scales and areas of dryness along the north and southwest coasts at longer time scales. Dry areas were evident along the extreme west coast, as seen in GRACE groundwater and soil moisture data and in the Australian Combined Drought Indicator analyses.
In South America, above-normal precipitation fell over parts of the drought areas in April, but precipitation amounts were below normal across many other areas. Temperatures were above normal across most of the continent. The April warmth, combined with above-normal temperatures continent-wide in March, resulted in the sixth warmest March–April on record. South America had the 13th-warmest May–April 12-month period. The ESI showed enhanced evapotranspiration from eastern Brazil and Bolivia southward through Argentina and Chile. The SPI and SPEI maps showed dry areas at 1- to 3-month time scales in Venezuela, Peru, and Brazil, but dry conditions were especially pronounced and widespread from Peru and western Brazil southward at 1 to 48 months. Satellite (GRACE) observations revealed extensive areas of low groundwater and soil moisture from Venezuela to Brazil and southern Peru to the southern tip of the continent. Drought in southern and western Brazil was confirmed on the Brazilian Drought Monitor.
In North America, April was drier than normal from northwestern Mexico and the southwestern U.S. to the U.S. Ohio Valley, across much of central Canada and the Canadian Atlantic coastal provinces, and from southern Mexico to all of Central America. The southwestern U.S. was wet earlier in the year, resulting in a dry area that extended from northern Mexico to the U.S. central Plains at 2- to 24-month time scales. Much of western to central Canada, and some eastern portions, as well as Florida and much of the Gulf of Mexico and Caribbean region, were drier than normal at 2 to 24 months. At longer time scales, dryness in Canada was limited to southern areas along the U.S. border, with the dryness extending across the border into northern parts of the U.S. Most of Mexico was dry for much of the last 36 to 72 months.
In the U.S., parts of the West and much of the southern to central Plains were dry at 36 to 48 months, with dryness limited to the western U.S. at longer time scales. April was warmer than normal across the eastern half of the U.S. and over eastern and northern Canada, and this enhanced evapotranspiration over the eastern U.S. as seen in the ESI, but many of the drought areas in North America were near to cooler than normal in April. Cold-air outbreaks in recent months have reduced the temperature rank for North America, but the last 12 months still ranked as the seventh warmest May–April in the NCEI record. Excessive heat in earlier years resulted in the last 48 months (May 2019–April 2023) tying with 2013–17 as the third warmest such 48-month period. GRACE satellite data revealed low groundwater and soil moisture levels over north central and western to central Canada, the interior western portions of the U.S., from the central and southern Plains in the U.S. to central Mexico, and from Mexico's Yucatan Peninsula to most of Central America.
The North American Drought Monitor product depicted drought across much of western to central Canada; the central U.S. and parts of the U.S. West; parts of the Gulf of Mexico coast; and much of Mexico. The Caribbean Regional Climate Center SPI maps showed dryness across Caribbean islands at 1- to 12-month time scales. According to media reports (Reuters), lakes near the Panama Canal were low, leading to draft restrictions on the largest ships passing through the canal. The Farm Journal reported that, in the U.S., drought has kept the contraction phase for the U.S. beef cow inventory going since 2020, with the beef cow inventory reaching a 60-year low at the start of 2023 at 28.9 million head, down 3.6% from the previous year. Cattle may continue to be culled in the next few months if drought persists. The drought in the U.S. Plains was reducing crop yields, as reported by farmers from South Dakota to Oklahoma.
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