Direct relations between solar activity and atmospheric circulation, its effect on changes of weather and climate

In this study, a global atmospheric model, Specified Dynamics Whole Atmosphere Community Climate Model with thermosphere and ionosphere eXtension (SD-WACCM-X), and the residual circulation principle were used to study the global atmospheric circulation from the lower to upper atmosphere (~500 km) from 2002 to 2019. Our analysis shows that the atmospheric circulation is clearly influenced by solar activity, especially in the upper atmosphere, which is mainly characterized by an enhanced atmospheric circulation in years with high solar activity. The atmospheric circulation in the upper atmosphere also exhibits an ~11 year period, and its variation is highly correlated with the temporal variation in the F10.7 solar index during the same time series, with a maximum correlation coefficient of up to more than 0.9. In the middle and lower atmosphere, the impact of solar activity on the atmospheric circulation is not as obvious as in the upper atmosphere due to some atmospheric activities such as the Quasi-Biennial Oscillation (QBO), El Niño–Southern Oscillation (ENSO), sudden stratospheric warming (SSW), volcanic forcing, and so on. By comparing the atmospheric circulation in different latitudinal regions between years with high and low solar activity, we found the atmospheric circulation in mid- and high-latitude regions is more affected by solar activity than in low-latitude and equatorial regions. In addition, clear seasonal variation in atmospheric circulation was detected in the global atmosphere, excluding the regions near 10−4 hPa and the lower atmosphere, which is mainly characterized by a flow from the summer hemisphere to the winter hemisphere. In the middle and low atmosphere, the atmospheric circulation shows a quasi-biennial oscillatory variation in the low-latitude and equatorial regions. This work provides a referable study of global atmospheric circulation and demonstrates the impacts of solar activity on global atmospheric circulation.

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Solar modulation of flood frequency in central Europe during spring and summer on interannual to multi-centennial timescales

Climate of the Past ◽

10.5194/cp-12-799-2016 ◽

2016 ◽

Vol 12 (3) ◽

pp. 799-805 ◽

Cited By ~ 19

Author(s):

Markus Czymzik ◽

Raimund Muscheler ◽

Achim Brauer

Keyword(s):

Solar Activity ◽

Atmospheric Circulation ◽

Central Europe ◽

Empirical Support ◽

Total Solar Irradiance ◽

Flood Frequency ◽

Solar Modulation ◽

Top Down ◽

Discharge Data ◽

Atmospheric Circulation Patterns

Abstract. Solar influences on climate variability are one of the most controversially discussed topics in climate research. We analyze solar forcing of flood frequency in central Europe during spring and summer on interannual to multi-centennial timescales, integrating daily discharge data of the River Ammer (southern Germany) back to AD 1926 (∼  solar cycles 16–23) and the 5500-year flood layer record from varved sediments of the downstream Ammersee. Flood frequency in the River Ammer discharge record is significantly correlated to changes in solar activity when the flood record lags the solar signal by 2–3 years (2-year lag: r = −0.375, p = 0.01; 3-year lag: r = −0.371, p = 0.03). Flood layer frequency in the Ammersee sediment record depicts distinct multi-decadal variations and significant correlations to a total solar irradiance reconstruction (r = −0.4, p <  0.0001) and 14C production rates (r = 0.37, p <  0.0001), reflecting changes in solar activity. On all timescales, flood frequency is higher when solar activity is reduced. In addition, the configuration of atmospheric circulation associated with periods of increased River Ammer flood frequency broadly resembles that during intervals of reduced solar activity, as expected to be induced by the so-called solar top-down mechanism by model studies. Both atmospheric patterns are characterized by an increase in meridional airflow associated with enhanced atmospheric blocking over central Europe. Therefore, the significant correlations as well as similar atmospheric circulation patterns might provide empirical support for a solar influence on hydroclimate extremes in central Europe during spring and summer by the so-called solar top-down mechanism.

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Atmospheric Circulation and Climatic Variability

The Physical Geography of South America ◽

10.1093/oso/9780195313413.003.0010 ◽

2007 ◽

Cited By ~ 2

Author(s):

René D. Garreaud ◽

Patricio Aceituno

Keyword(s):

South America ◽

Atmospheric Circulation ◽

Amazon Basin ◽

Southern Oscillation ◽

Climatic Variability ◽

Climatic Conditions ◽

The West ◽

The Andes ◽

Weather And Climate ◽

Atmospheric Phenomena

Regional variations in South America’s weather and climate reflect the atmospheric circulation over the continent and adjacent oceans, involving mean climatic conditions and regular cycles, as well as their variability on timescales ranging from less than a few months to longer than a year. Rather than surveying mean climatic conditions and variability over different parts of South America, as provided by Schwerdtfeger and Landsberg (1976) and Hobbs et al. (1998), this chapter presents a physical understanding of the atmospheric phenomena and precipitation patterns that explain the continent’s weather and climate. These atmospheric phenomena are strongly affected by the topographic features and vegetation patterns over the continent, as well as by the slowly varying boundary conditions provided by the adjacent oceans. The diverse patterns of weather, climate, and climatic variability over South America, including tropical, subtropical, and midlatitude features, arise from the long meridional span of the continent, from north of the equator south to 55°S. The Andes cordillera, running continuously along the west coast of the continent, reaches elevations in excess of 4 km from the equator to about 40°S and, therefore, represents a formidable obstacle for tropospheric flow. As shown later, the Andes not only acts as a “climatic wall” with dry conditions to the west and moist conditions to the east in the subtropics (the pattern is reversed in midlatitudes), but it also fosters tropical-extratropical interactions, especially along its eastern side. The Brazilian plateau also tends to block the low-level circulation over subtropical South America. Another important feature is the large area of continental landmass at low latitudes (10°N–20°S), conducive to the development of intense convective activity that supports the world’s largest rain forest in the Amazon basin. The El Niño–Southern Oscillation phenomenon, rooted in the ocean-atmosphere system of the tropical Pacific, has a direct strong influence over most of tropical and subtropical South America. Similarly, sea surface temperature anomalies over the Atlantic Ocean have a profound impact on the climate and weather along the eastern coast of the continent. In this section we describe the long-term annual and monthly mean fields of several meteorological variables.

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New indications of the 4-month oscillation in solar activity, atmospheric circulation and Earth's rotation

Solar Physics ◽

10.1007/bf00670234 ◽

1995 ◽

Vol 156 (2) ◽

pp. 395-404 ◽

Cited By ~ 1

Author(s):

D. Djurovic ◽

P. P�quet

Keyword(s):

Solar Activity ◽

Atmospheric Circulation ◽

Earth’S Rotation ◽

Earth's Rotation

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