California droughts are often caused by high-amplitude and persistent ridges near and off the west coast of North America without apparent connections with ENSO. Here with a hierarchy of climate models, it is demonstrated that extreme ridges in this region are associated with a continuum of zonal wavenumber-5 circumglobal teleconnection patterns that originate from midlatitude atmospheric internal dynamics. Although tropical diabatic heating anomalies are not essential to the formation and maintenance of these wave patterns, certain persistent heating anomalies may double the probability of ridges with amplitudes in the 90th percentile occurring on interannual time scales. Those heating anomalies can be caused by either natural variability or possibly by climate change, and they do not necessarily depend on ENSO. The extreme ridges that occurred during the 2013/14 and 2014/15 winters could be examples of ridges produced by heating anomalies that are not associated with ENSO. This mechanism could provide a source of subseasonal-to-interannual predictability beyond the predictability provided by ENSO.
Application of random sampling techniques to composite differences between 18 El Niño and 14 La Niña events observed since 1920 reveals considerable...
2017 | Journal of the Atmospheric Sciences, 74(6), 1799-1817.
Description:
Column moisture and moist static energy (MSE) budgets have become common tools in the study of the processes responsible for the maintenance and evolu...
This study investigates the intraseasonal variations of the Northern Hemispheric storm track associated with the Madden–Julian oscillation (MJO) dur...
This study provides an analysis of the Mediterranean Sea surface energy budget using nine surface heat flux climatologies. The ensemble mean estimatio...
Changes in precipitation characteristics directly affect society through their impacts on drought and floods, hydro-dams, and urban drainage systems. ...
2017 | Journal of the Atmospheric Sciences, 74(6), 1735-1755
Description:
The occurrence of boreal winter Rossby wave breaking (RWB) along with the quantitative role of synoptic transient eddy momentum and heat fluxes direct...
Atmospheric rivers (ARs) have significant hydrometeorological impacts on the U.S. West Coast. This study presents the connection between the character...
Part I of this study examines the relationship among winter cold anomalies over Eurasia, Ural blocking (UB), and the background conditions associated ...
This paper demonstrates that an operational forecast model can skillfully predict week-3–4 averages of temperature and precipitation over the contig...
This study provides an assessment of the uncertainty in ocean surface (OS) freshwater budgets and variability using evaporation E and precipitation P ...
Using NASA Aqua MODIS and AIRS data, the relationship between low-level cloud cover (cloud top below the 700-hPa level) and boundary layer stability i...
2017 | Journal of Hydrometeorology, 18(7), 1943-1962
Description:
The U.S. Drought Monitor (USDM) classifies drought into five discrete dryness/drought categories based on expert synthesis of numerous data sources. I...
This observationally based study demonstrates the importance of the delayed hydrological response of snow cover and snowmelt over the Eurasian region ...
Seasonal climate predictions are formulated from known present conditions and simulate the near‐term climate for approximately a year in the future....
This study investigates the characteristics of extratropical Rossby wave breaking (RWB) during the Atlantic hurricane season and its impacts on Atlant...
The observed Madden–Julian oscillation (MJO) tends to propagate eastward across the Maritime Continent from the eastern equatorial Indian Ocean to t...
2017 | Journal of Hydrometeorology, 18(7), 1963-1982
Description:
Probabilistic forecasts of U.S. Drought Monitor (USDM) intensification over 2-, 4-, and 8-week time periods are developed based on recent anomalies in...
During 2013–15, prolonged near-surface warming in the northeastern Pacific was observed and has been referred to as the Pacific warm blob. Here, sta...
2016 | Bulletin of the American Meteorological Society, 98(7), 1363-1382.
Description:
The El Niño of 2015/16 was among the strongest El Niño events observed since 1950 and took place almost two decades after the previous major event i...
The canonical relationship between the length and the total seasonal rainfall anomalies of the Indian summer monsoon (ISM) is the association of the l...
A long-term climatology of cloudiness over the Norwegian, Barents, and Kara Seas (NBK) based on visual surface observations is presented. Annual mean ...
Links with this icon indicate that you are leaving the NOAA website.
The National Oceanic and Atmospheric Administration
(NOAA) cannot attest to the accuracy of a non-federal
website.
Linking to a non-federal Website does not constitute an
endorsement by NOAA or any of its employees of the sponsors
or the information and products presented on the website.
You will be subject to the destination website's privacy
policy when you follow the link.
NOAA is not responsible for Section 508 compliance
(accessibility) on other federal or private websites.