Climate

Description of time series:

The Oceanic Niño Index (ONI) is NOAA’s primary index for monitoring the El Niño-Southern Oscillation climate pattern. It is based on Sea Surface Temperature values in a particular part of the central equatorial Pacific, which scientists refer to as the Niño 3.4 region. Positive values of this indicator, greater than +0.5, indicate warm El Niño conditions, while negative values, less than -0.5, indicate cold La Niña conditions. The ONI indicator changed from positive to negative during the summer of 2020, and is now showing La Niña conditions.

 Description of gauge:

The unitless two-way gauge depicts the most recent seasonal value for the ONI showing how far it is above or below the median value of the entire time series. High values in either direction mean extreme variation from the median value of the entire time series. 

 Description of El Niño-Southern Oscillation (ENSO):

El Niño and La Niña are opposite phases of the El Niño-Southern Oscillation (ENSO), a cyclical condition occurring across the Equatorial Pacific Ocean with worldwide effects on weather and climate. During an El Niño, surface waters in the central and eastern equatorial Pacific become warmer than average and the trade winds - blowing from east to west - greatly weaken. During a La Niña, surface waters in the central and eastern equatorial Pacific become much cooler, and the trade winds become much stronger. El Niños and La Niñas generally last about 6 months but can extend up to  2 years. The time between events is irregular, but generally varies between 2-7 years. To monitor ENSO conditions, NOAA operates a network of buoys, which measure temperature, currents, and winds in the equatorial Pacific. 

This climate pattern impacts people and ecosystems around the world. Interactions between the ocean and atmosphere alter weather globally and can result in severe storms or mild weather, drought or flooding. Beyond “just” influencing the weather and ocean conditions, these changes can produce secondary results that influence food supplies and prices, forest fires and flooding, and create additional economic and political consequences. For example, along the west coast of the U.S., warm El Niño events are known to inhibit the delivery of nutrients from subsurface waters, suppressing local fisheries. 

 Data:

Climate indicator data was accessed from the NOAA Climate Prediction Center (https://origin.cpc.ncep.noaa.gov/products/analysis_monitoring/ensostuff…). The data are plotted in degrees Celsius and represent Sea Surface Temperature anomalies averaged across the so-called Niño 3.4 region in the east-central tropical Pacific between 120°-170°W.

Description of time series:

Like the Oceanic Niño Index, positive MEI values indicate warm, El Niño conditions and negative MEI values indicate cold, La Niña conditions. The MEI indicator changed from positive to negative during the summer of 2020, and is now showing La Niña conditions.

Description of gauge:

The unitless two-way gauge depicts the most recent seasonal value for the MEI showing how far it is above or below the median value of the entire time series. High values in either direction mean extreme variation from the median value of the entire time series. 

Description of Multivariate El Niño-Southern Oscillation Index:

The Multivariate El Niño-Southern Oscillation Index (MEI) is a more holistic representation of the atmospheric and oceanic conditions that occur during ENSO events and characterizes their intensity. MEI is determined from five variables from the central and eastern equatorial Pacific (Sea-level pressure, surface wind components, sea surface temperature, surface air temperature, and cloudiness) while ENSO is calculated from only two (sea surface temperature and trade wind strength). This index is calculated twelve times per year for each sliding bi-monthly season i.e. Dec-Jan, Jan-Feb, Feb-Mar, etc. We present data from the Pacific Islands, Alaska, and California Current regions.

This climate condition impacts people and ecosystems across the globe and each of the indicators presented here. Interactions between the ocean and atmosphere alter weather around the world and can result in severe storms or mild weather, drought, or flooding. Beyond “just” influencing the weather and ocean conditions, these changes can produce secondary results that influence food supplies and prices, forest fires and flooding, and create additional economic and political consequences.

Data:

Climate indicator data was accessed from the NOAA’s Earth Systems Research Laboratory (https://psl.noaa.gov/enso/mei/). The data plotted are unitless anomalies.

Description of time series:

Positive PDO values typically mean cold, La Niña conditions, and negative PDO values typically mean warm, El Niño conditions. During the last five years, the PDO indicator shows a significant downward trend.

Description of gauge:

The unitless two-way gauge depicts whether the average of the last 5 years of data for the climate indicator is above or below the median value of the entire time series. High values in either direction mean extreme variation from the median value of the entire time series. 

Description of Pacific Decadal Oscillation (PDO):

The Pacific Decadal Oscillation (PDO) is a long-term pattern of Pacific climate variability. The extreme phases of this climatic condition are classified as warm or cool, based on deviations from average ocean temperature in the northeast and central North Pacific Ocean. When the PDO has a positive value, sea surface temperatures are below average (cool) in the interior North Pacific and warm along the Pacific Coast. When the PDO has a negative value, the climate patterns are reversed, with above average sea surface temperatures in the interior and sea surface temperatures below average along the North American coast. The PDO waxes and wanes; warm and cold phases may persist for decades. Major changes in northeast Pacific marine ecosystems have been correlated with phase changes in the PDO. Warm phases have seen enhanced coastal ocean biological productivity in Alaska and inhibited productivity off the west coast of the United States, while cold PDO phases have seen the opposite, north-south pattern of marine ecosystem productivity. We present data from the Pacific Islands, Alaska, and California Current regions.

This climate condition impacts people and ecosystems across the globe and each of the indicators presented here. Interactions between the ocean and atmosphere alter weather around the world and can result in severe storms or mild weather, drought, or flooding. Beyond “just” influencing the weather and ocean conditions, these changes can produce secondary results that influence food supplies and prices, forest fires and flooding, and create additional economic and political consequences.

Data:

Climate indicator data was accessed from the NOAA Climate Prediction Center (https://www.cpc.ncep.noaa.gov/data/teledoc/nao.shtmlftp://ftp.cpc.ncep.noaa.gov/wd52dg/data/indices/nao_index.tim). The data plotted are unitless and based on Sea Surface Temperature anomalies averaged across a given region.

Description of time series:

Positive EP-NP values mean above-average surface temperatures over the eastern North Pacific, and below-average temperatures over the central North Pacific and eastern North America and the opposite for negative EP-NP values. During the last five years, the EP-NP indicator shows no significant trend.

Description of gauge:

The unitless two-way gauge depicts whether the average of the last 5 years of data for the climate indicator is above or below the median value of the entire time series. High values in either direction mean extreme variation from the median value of the entire time series. 

Description of East Pacific/ North Pacific Teleconnection Pattern Index:

The East Pacific/ North Pacific Teleconnection Pattern Index is a measure of climate variability. Positive EP-NP values mean above-average surface temperatures over the eastern North Pacific, and below-average temperatures over the central North Pacific and eastern North America and the opposite for negative EP-NP values.

This climate condition impacts people and ecosystems across the globe and each of the indicators presented here. Interactions between the ocean and atmosphere alter weather around the world and can result in severe storms or mild weather, drought, or flooding. Beyond “just” influencing the weather and ocean conditions, these changes can produce secondary results that influence food supplies and prices, forest fires and flooding, and create additional economic and political consequences.

Data:

Climate indicator data was accessed from the NOAA Climate Prediction Center (https://www.cpc.ncep.noaa.gov/data/teledoc/nao.shtmlftp://ftp.cpc.ncep.noaa.gov/wd52dg/data/indices/nao_index.tim). The data plotted are unitless anomalies and averaged across a given region. 

Description of time series:

Positive NAO values mean significantly warmer winters over the upper Midwest and New England and negative NAO values can mean cold winter outbreaks and heavy snowstorms. During the last five years, the NAO indicator shows no significant trend.

Description of gauge:

The unitless two-way gauge depicts whether the average of the last 5 years of data for the climate indicator is above or below the median value of the entire time series. High values in either direction mean extreme variation from the median value of the entire time series. 

Description of North Atlantic Oscillation (NAO):

The North Atlantic Oscillation (NAO) Index measures the relative strengths and positions of a permanent low-pressure system over Iceland (the Icelandic Low) and a permanent high-pressure system over the Azores (the Azores High). When the index is positive (NAO+) significantly warmer winters can occur over the upper Midwest and New England. On the East Coast of the United States a NAO+ can also cause increased rainfall, and thus warmer, less saline surface water. This prevents nutrient-rich upwelling, which reduces productivity. When the NAO index is negative, the upper central and northeastern portions of the United States can incur winter cold outbreaks and heavy snowstorms. We present data for the Northeast, Southeast, Gulf of Mexico, and Caribbean regions.

This climate condition impacts people and ecosystems across the globe and each of the indicators presented here. Interactions between the ocean and atmosphere alter weather around the world and can result in severe storms or mild weather, drought, or flooding. Beyond “just” influencing the weather and ocean conditions, these changes can produce secondary results that influence food supplies and prices, forest fires and flooding, and create additional economic and political consequences.

Data:

Climate indicator data was accessed from the NOAA Climate Prediction Center (https://www.cpc.ncep.noaa.gov/data/teledoc/nao.shtmlftp://ftp.cpc.ncep.noaa.gov/wd52dg/data/indices/nao_index.tim). The data plotted are unitless anomalies and averaged across a given region.

Description of time series:

Positive AMO values indicate the warm phase and negative AMO values indicate the cold phase. During the last five years, the AMO indicator shows no significant trend.

Description of gauge:

The unitless two-way gauge depicts whether the average of the last 5 years of data for the climate indicator is above or below the median value of the entire time series. High values in either direction mean extreme variation from the median value of the entire time series. 

Description of Atlantic Multidecadal Oscillation (AMO):

The Atlantic Multidecadal Oscillation is a series of long-duration changes in the North Atlantic sea surface temperature, with cool and warm phases that may last for 20-40 years. Most of the Atlantic between the equator and Greenland changes in unison. Some areas of the North Pacific also seem to be affected. 

This broadscale climate condition affects air temperatures and rainfall over much of the Northern Hemisphere. It is also related to major droughts in the Midwest and the Southwest of the U.S. In the warm phase, these droughts tend to be more frequent and/or severe. Vice-versa for the cold phase. During the warm phases the number of tropical storms that mature into severe hurricanes is much greater than during cool phases. We present data for the Northeast, Southeast, and Gulf of Mexico regions..

This climate condition impacts people and ecosystems across the globe and each of the indicators presented here. Interactions between the ocean and atmosphere alter weather around the world and can result in severe storms or mild weather, drought, or flooding. Beyond “just” influencing the weather and ocean conditions, these changes can produce secondary results that influence food supplies and prices, forest fires and flooding, and create additional economic and political consequences.

Data:

Climate indicator data was accessed from the NOAA Climate Prediction Center (https://www.cpc.ncep.noaa.gov/data/teledoc/nao.shtmlftp://ftp.cpc.ncep.noaa.gov/wd52dg/data/indices/nao_index.tim). The data plotted are unitless anomalies and averaged across a given region.