Estimate of local features of long-term variations in cloud cover over the territory of Siberia using results of its climatic zoning according to total and low-level cloud regimes

2015 ◽  
Vol 28 (3) ◽  
pp. 265-272 ◽  
Author(s):  
V. S. Komarov ◽  
G. G. Matvienko ◽  
S. N. Il’in ◽  
N. Ya. Lomakina
Keyword(s):  
Cloud Cover ◽  
Local Features ◽  
Low Level ◽  
Cloud Regimes ◽  
Climatic Zoning ◽  
Long Term Variations

scholarly journals Climatic factors contributing to long-term variations of fine dust concentration in the United States

2017 ◽  
Author(s):  
Bing Pu ◽  
Paul Ginoux
Keyword(s):  
Great Plains ◽  
The United States ◽  
Dust Concentration ◽  
Dust Particles ◽  
Positive Trend ◽  
Fine Dust ◽  
Low Level ◽  
Low Level Jet ◽  
Long Term Variations

Abstract. High concentration of dust particles can cause respiratory problems and increase non-accidental mortality. Studies found fine dust (with aerodynamic diameter less than 2.5 microns) is an important component of the total PM2.5 mass in the western and central U.S. in spring and summer and has positive trends. This work examines factors influencing long-term variations of fine dust concentration in the U.S. using station data from the Interagency Monitoring Protected Visual Environments (IMPROVE) network during 1990–2015. The variations of the fine dust concentration can be largely explained by the variations of precipitation, surface bareness, and 10 m wind speed. Moreover, including convective parameters such as convective inhibition (CIN) and convective available potential energy (CAPE) better explains the variations and trends over the Great Plains from spring to fall. While the positive trend of fine dust concentration in the Southwest in spring is associated with precipitation deficit, the increasing of fine dust over the central Great Plains in summer is largely associated with an enhancing of CIN and a weakening of CAPE, which are related to increased atmospheric stability due to surface drying and lower troposphere warming. The positive trend of the Great Plains low-level jet also contributes to the increasing of fine dust concentration in the central Great Plains in summer via its connections with surface winds and CIN. Summer dusty days in the central Great Plains are usually associated with a westward extension of the North Atlantic subtropical high that intensifies the Great Plains low-level jet and also results in a stable atmosphere with subsidence and reduced precipitation.

scholarly journals Variations in Cloud Cover and Cloud Types over the Ocean from Surface Observations, 1954–2008

2011 ◽  
Vol 24 (22) ◽  
pp. 5914-5934 ◽  
Author(s):  
Ryan Eastman ◽  
Stephen G. Warren ◽  
Carole J. Hahn
Keyword(s):  
Time Series ◽  
Surface Temperature ◽  
Negative Correlation ◽  
Cloud Cover ◽  
Sea Surface ◽  
Interannual Variations ◽  
Total Cloud Cover ◽  
Marine Stratus ◽  
Long Term Variations

Abstract Synoptic weather observations from ships throughout the World Ocean have been analyzed to produce a climatology of total cloud cover and the amounts of nine cloud types. About 54 million observations contributed to the climatology, which now covers 55 years from 1954 to 2008. In this work, interannual variations of seasonal cloud amounts are analyzed in 10° grid boxes. Long-term variations O(5–10 yr), coherent across multiple latitude bands, remain present in the updated cloud data. A comparison to coincident data on islands indicates that the coherent variations are probably spurious. An exact cause for this behavior remains elusive. The globally coherent variations are removed from the gridbox time series using a Butterworth filter before further analysis. Before removing the spurious variation, the global average time series of total cloud cover over the ocean shows low-amplitude, long-term variations O(2%) over the 55-yr span. High-frequency, year-to-year variation is seen O(1%–2%). Among the cloud types, the most widespread and consistent relationship is found for the extensive marine stratus and stratocumulus clouds (MSC) over the eastern parts of the subtropical oceans. Substantiating and expanding upon previous work, strong negative correlation is found between MSC and sea surface temperature (SST) in the eastern North Pacific, eastern South Pacific, eastern South Atlantic, eastern North Atlantic, and the Indian Ocean west of Australia. By contrast, a positive correlation between cloud cover and SST is seen in the central Pacific. High clouds show a consistent low-magnitude positive correlation with SST over the equatorial ocean. In regions of persistent MSC, time series show decreasing MSC amount. This decrease could be due to further spurious variation within the data. However, the decrease combined with observed increases in SST and the negative correlation between marine stratus and sea surface temperature suggests a positive cloud feedback to the warming sea surface. The observed decrease of MSC has been partly but not completely offset by increasing cumuliform clouds in these regions; a similar decrease in stratiform and increase in cumuliform clouds had previously been seen over land. Interannual variations of cloud cover in the tropics show strong correlation with an ENSO index.

scholarly journals Climatic factors contributing to long-term variations in surface fine dust concentration in the United States

2018 ◽  
Vol 18 (6) ◽  
pp. 4201-4215 ◽  
Author(s):  
Bing Pu ◽  
Paul Ginoux
Keyword(s):  
Great Plains ◽  
Climatic Factors ◽  
The United States ◽  
Dust Concentration ◽  
Dust Particles ◽  
Fine Dust ◽  
Low Level ◽  
Low Level Jet ◽  
Long Term Variations

Abstract. High concentrations of dust particles can cause respiratory problems and increase non-accidental mortality. Studies found fine dust (with an aerodynamic diameter of less than 2.5 µm) is an important component of the total PM2.5 mass in the western and central US in spring and summer and has positive trends. This work examines climatic factors influencing long-term variations in surface fine dust concentration in the US using station data from the Interagency Monitoring Protected Visual Environments (IMPROVE) network during 1990–2015. The variations in the fine dust concentration can be largely explained by the variations in precipitation, surface bareness, and 10 m wind speed. Moreover, including convective parameters such as convective inhibition (CIN) and convective available potential energy (CAPE) that reveal the stability of the atmosphere better explains the variations and trends over the Great Plains from spring to fall. While the positive trend of fine dust concentration in the southwestern US in spring is associated with precipitation deficit, the increase in fine dust over the central Great Plains in summer is largely associated with enhanced CIN and weakened CAPE, which are caused by increased atmospheric stability due to surface drying and lower-troposphere warming. The strengthening of the Great Plains low-level jet also contributes to the increase in fine dust concentration in the central Great Plains in summer via its positive correlation with surface winds and negative correlation with CIN. Summer dusty days in the central Great Plains are usually associated with a westward extension of the North Atlantic subtropical high that intensifies the Great Plains low-level jet and also results in a stable atmosphere with subsidence and reduced precipitation.

41. Diffusion Badges as a Long-Term, Low-Level Method of Ambient Air Analysis

2005 ◽  
Author(s):  
K. Parker ◽  
S. Rose-Pehrsson ◽  
D. Kidwell
Keyword(s):  
Ambient Air ◽  
Air Analysis ◽  
Low Level ◽  
Level Method

Long-Term Unemployment in Poland in 2008-2012 - Tendencies, Structure and Selected Determinants

2013 ◽  
Vol 8 (4) ◽  
pp. 347-359
Author(s):  
Leszek Kucharski
Keyword(s):  
Secondary Education ◽  
Young People ◽  
Level Of Education ◽  
Low Level ◽  
Increased Risk

This study presents the structure and tendencies in long-term unemployment in Poland in the years 2008-2012. This study identifies the groups of people with an increased risk of long-term unemployment. The analyses produced the following conclusions. The groups with the highest risk of long-term unemployment include: singles, people aged of 55 and above and people with a low level of education. Young people with university and general secondary education faced the lowest risk of long-term unemployment. 

Case Evidence: Conflict Trajectories in Indonesia, Ivory Coast, and Syria

2018 ◽  
Author(s):  
Jaroslav Tir ◽  
Johannes Karreth
Keyword(s):  
Civil War ◽  
Ivory Coast ◽  
Armed Conflicts ◽  
East Timor ◽  
Intergovernmental Organizations ◽  
Crisis Resolution ◽  
Low Level ◽  
Qualitative Evidence ◽  
The Government

Two low-level armed conflicts, Indonesia’s East Timor and Ivory Coast’s post-2010 election crises, provide detailed qualitative evidence of highly structured intergovernmental organizations (IGOs) engaging in effective civil warpreventing activities in member-states. Highly structured IGOs threatened and sanctioned each of these states and offered (long-term) benefits conditional on successful crisis resolution. The governments were aware of and responded to these IGOs’ concerns, as did the rebels in these respective cases. The early stages of the conflict in Syria in 2011 provide a counterpoint. With Syria’s limited engagement in only few highly structured IGOs, the Syrian government ignored international calls for peace. And, without highly structured IGOs’ counterweight to curtail the government, the rebels saw little reason to stop their armed resistance. The result was a brutal and deadly civil war that continues today.

scholarly journals Vodnyi: a Long-term, Low-level Radiation Exposure Field Site in Russia

2003 ◽  
Vol 38 (4) ◽  
pp. 332-343 ◽  
Author(s):  
Anatoly I. TASKAEV ◽  
Edward R. LANDA ◽  
Denis V. GURYEV ◽  
Natalia GOLOVKO BUTLER ◽  
Thomas F. KRAEMER
Keyword(s):  
Radiation Exposure ◽  
Field Site ◽  
Low Level ◽  
Exposure Field

Repeated Occupational Exposure to Low-level Blast in the Canadian Armed Forces: Effects on Hearing, Balance, and Ataxia

2021 ◽  
Author(s):  
Ann Nakashima ◽  
Oshin Vartanian ◽  
Shawn G Rhind ◽  
Kristen King ◽  
Catherine Tenn ◽  
...  
Keyword(s):  
Hearing Loss ◽  
Occupational Exposure ◽  
Armed Forces ◽  
Cross Sectional ◽  
Low Level ◽  
Additional Information ◽  
Adverse Health Effects ◽  
Blast Overpressure ◽  
Blast Exposure

ABSTRACT Introduction Recently, there has been increasing concern about the adverse health effects of long-term occupational exposure to low-level blast in military personnel. Occupational blast exposure occurs routinely in garrison through use of armaments and controlled blast detonations. In the current study, we focused on a population of breaching instructors and range staff. Breaching is a tactical technique that is used to gain entry into closed spaces, often through the use of explosives. Materials and Methods Initial measurements of blast overpressure collected during breaching courses found that up to 10% of the blasts for range staff and up to 32% of the blasts for instructors exceeded the recommended 3 psi exposure limit. Using a cross-sectional design, we used tests of balance, ataxia, and hearing to compare a sample of breachers (n = 19) to age-and sex-matched military controls (n = 19). Results There were no significant differences between the two groups on the balance and ataxia tests, although the average scores of both groups were lower than would be expected in a normative population. The prevalence of hearing loss was low in the breacher group (4 of 19), and hearing thresholds were not significantly different from the controls. However, the prevalence of self-reported tinnitus was significantly higher in the breacher group (12 of 19) compared with the controls (4 of 19), and all breachers who were identified as having hearing loss also reported tinnitus. Conclusions Our results suggest that basic tests of balance, ataxia, and hearing on their own were not sensitive to the effects of long-term occupational exposure to low-level blast. Some of the blast exposure levels exceeded limits, and there was a significant association of exposure with tinnitus. Future studies should supplement with additional information including exposure history and functional hearing assessments. These findings should be considered in the design of future acute and longitudinal studies of low-level blast exposure.

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