The change of MJO teleconnection under the global warming

2020 ◽  
Author(s):  
Wan-Ling Tseng ◽  
Huang-Hsiung Hsu ◽  
Li-Chiang Jiang ◽  
Chiung-Wen June Chang ◽  
Ben-Jei Tsuang ◽  
...  
Keyword(s):  
Global Warming ◽  
Seasonal Forecast ◽  
Jet Stream ◽  
Madden Julian Oscillation ◽  
The North ◽  
Warming Climate ◽  
Polar Area ◽  
The Mean ◽  
Key Features ◽  
The Relationship

<p>Global warming’s impact on the Madden-Julian Oscillation (MJO) is assessed using one of the few models capable in reproducing its key features. In a warmer climate predicted for the end of the century, it has been proved the MJO increases in amplitude and frequency, showing a more circumglobal propagation tendency. Here, we examine the MJO teleconnection and its extratropical response under the warmer climate by the time-slide experiments. The extratropics impact on different phase is shifted through the change of the mean atmospheric circulation. The strengthening of the midlatitude jet stream leads to the zonal extended wave propagation. It results the stronger variability of the atmospheric river to the America west coast. Moreover, the relationship with the NAO and PNA is weaker but the stronger fluctuation is shown in the polar area. This suggests the teleconnection of the North America weather by the tropical convection is going to change in the warming climate. It is essential to consider in the further projection and subseasonal to seasonal forecast.</p>

scholarly journals A Taxonomic Review of Patient Complaints in Adult Hospital Medicine

2021 ◽  
Vol 8 ◽  
pp. 237437352110073
Author(s):  
Richard M Elias ◽  
Karen M Fischer ◽  
Mustaqeem A Siddiqui ◽  
Trevor Coons ◽  
Cindy A Meyerhofer ◽  
...  
Keyword(s):  
Hospital Admissions ◽  
Hospital Medicine ◽  
Patient Complaints ◽  
Period Data ◽  
The Mean ◽  
Key Features ◽  
Person Characteristics ◽  
The Relationship ◽  
Adult Hospital

Previous studies show that patient complaints can identify gaps in quality of care, but it is difficult to identify trends without categorization. We conducted a review of complaints relating to admissions on hospital internal medicine (HIM) services over a 26-month period. Data were collected on person characteristics and key features of the complaint. The complaints were also categorized into a previously published taxonomy. Seventy-six unsolicited complaints were identified, (3.5 per 1000 hospital admissions). Complaints were more likely on resident services. The mean duration between encounter and complaint was 18 days, and it took an average of 12 days to resolve the complaint. Most patients (59%) had a complaint in the Relationship domain. Thirty-nine percent of complaints mentioned a specific clinician. When a clinician was mentioned, complaints regarding communication and humaneness predominated (68%). The results indicate that the efforts to reduce patient complaints in HIM should focus on the Relationships domain.

scholarly journals Understanding Bjerknes Compensation in Meridional Heat Transports and the Role of Freshwater in a Warming Climate

2018 ◽  
Vol 31 (12) ◽  
pp. 4791-4806 ◽  
Author(s):  
Qianzi Yang ◽  
Yingying Zhao ◽  
Qin Wen ◽  
Jie Yao ◽  
Haijun Yang
Keyword(s):  
Global Warming ◽  
North Atlantic ◽  
Coupled Model ◽  
Phase Changes ◽  
Box Model ◽  
Freshwater Flux ◽  
The North ◽  
Warming Climate ◽  
Transient Period ◽  
The North Atlantic

The Bjerknes compensation (BJC) under global warming is studied using a simple box model and a coupled Earth system model. The BJC states the out-of-phase changes in the meridional atmosphere and ocean heat transports. Results suggest that the BJC can occur during the transient period of global warming. During the transient period, the sea ice melting in the high latitudes can cause a significant weakening of the Atlantic meridional overturning circulation (AMOC), resulting in a cooling in the North Atlantic. The meridional contrast of sea surface temperature would be enhanced, and this can eventually enhance the Hadley cell and storm-track activities in the Northern Hemisphere. Accompanied by changes in both ocean and atmosphere circulations, the northward ocean heat transport in the Atlantic is decreased while the northward atmosphere heat transport is increased, and the BJC occurs in the Northern Hemisphere. Once the freshwater influx into the North Atlantic Ocean stops, or the ocean even loses freshwater because of strong heating in the high latitudes, the AMOC would recover. Both the atmosphere and ocean heat transports would be enhanced, and they can eventually recover to the state of the control run, leading to the BJC to become invalid. The above processes are clearly demonstrated in the coupled model CO2 experiment. Since it is difficult to separate the freshwater effect from the heating effect in the coupled model, a simple box model is used to understand the BJC mechanism and freshwater’s role under global warming. In a warming climate, the freshwater flux into the ocean can cool the global surface temperature, mitigating the temperature rise. Box model experiments indicate clearly that it is the freshwater flux into the North Atlantic that causes out-of-phase changes in the atmosphere and ocean heat transports, which eventually plays a stabilizing role in global climate change.

scholarly journals An Evaluation of Northern Australian Wet Season Rainfall Bursts in CMIP5 Models

2018 ◽  
Vol 31 (19) ◽  
pp. 7789-7802 ◽  
Author(s):  
Sugata Narsey ◽  
Michael J. Reeder ◽  
Christian Jakob ◽  
Duncan Ackerley
Keyword(s):  
Outgoing Longwave Radiation ◽  
Climate Models ◽  
Longwave Radiation ◽  
Cmip5 Models ◽  
Madden Julian Oscillation ◽  
Wet Season ◽  
The North ◽  
Coupled Climate Models ◽  
The Tropics ◽  
The Relationship

The simulation of northern Australian wet season rainfall bursts by coupled climate models is evaluated. Individual models produce vastly different amounts of precipitation over the north of Australia during the wet season, and this is found to be related to the number of bursts they produce. The seasonal cycle of bursts is found to be poor in most of the models evaluated. It is known that northern Australian wet season bursts are often associated with midlatitude Rossby wave packets and their surface signature as they are refracted toward the tropics. The relationship between midlatitude waves and the initiation of wet season bursts is simulated well by the models evaluated. Another well-documented influence on the initiation of northern Australian wet season bursts is the Madden–Julian oscillation (MJO). No model adequately simulated the tropical outgoing longwave radiation temporal–spatial patterns seen in the reanalysis-derived OLR. This result suggests that the connection between the MJO and the initiation of northern Australian wet season bursts in models is poor.

The Relationship between Glossina morsitans and the Evaporation Rate

1931 ◽  
Vol 22 (3) ◽  
pp. 383-384 ◽  
Author(s):  
T. A. M. Nash
Keyword(s):  
Seasonal Variations ◽  
Evaporation Rate ◽  
Glossina Morsitans ◽  
North East ◽  
The North ◽  
The Mean ◽  
The Relationship

In a recent paper by the writer (Bull. Ent. Res., xxi, 1930, pp. 201–256) it was shown that the apparent fly density varied according to season. It has now been found that these seasonal variations in the fly density can be correlated with the evaporation rate.The accompanying graph shows the mean monthly evaporation rate, and the mean monthly apparent fly density. The evaporation rate figures have been obtained from a Livingston atmometer at the Kikori Entomological Station. The fly figures have been taken from the North-East Kikori Round, because this fly-round is not subjected to large game movements and hence is considered to be the best for demonstrating the correlation between fly density and season.The graph deals with a period of eighteen months, and it is clear that a relationship does exist between the two curves.In June and July 1929, the fly density was at its maximum. Hence it is reasonable to postulate that, at this time, the evaporation rate was suited to the requirements of the fly community.

scholarly journals Statistical Comparison of Cloud and Aerosol Vertical Properties between Two Eastern China Regions Based on CloudSat/CALIPSO Data

2017 ◽  
Vol 2017 ◽  
pp. 1-12
Author(s):  
Yujun Qiu ◽  
Jing Wang ◽  
Keran Yang
Keyword(s):  
Eastern China ◽  
Mean Value ◽  
Cloud Layer ◽  
Ice Cloud ◽  
The North ◽  
Warm Cloud ◽  
Four Seasons ◽  
The Mean ◽  
The Relationship ◽  
Aerosol Extinction Coefficient

The relationship between cloud and aerosol properties was investigated over two 4° × 4° adjacent regions in the south (R1) and in the north (R2) in eastern China. The CloudSat/CALIPSO data were used to extract the cloud and aerosol profiles properties. The mean value of cloud occurrence probability (COP) was the highest in the mixed cloud layer (−40°C~0°C) and the lowest in the warm cloud layer (>0°C). The atmospheric humidity was more statistically relevant to COP in the warm cloud layer than aerosol condition. The differences in COP between the two regions in the mixed cloud layer and ice cloud layer (<−40°C) had good correlations with those in the aerosol extinction coefficient. A radar reflectivity factor greater than −10 dBZ occurred mainly in warm cloud layers and mixed cloud layers. A high-COP zone appeared in the above-0°C layer with cloud thicknesses of 2-3 km in both regions and in all the four seasons, but the distribution of the zonal layer in R2 was more continuous than that in R1, which was consistent with the higher aerosol optical thickness in R2 than in R1 in the above-0°C layer, indicating a positive correlation between aerosol and cloud probability.

scholarly journals Knowledge and awareness of a medical faculty students in Turkey about global warming, climate change and their consequences Türkiye’de bir tıp fakültesi öğrencilerinin küresel ısınma, iklim değişikliği ve sonuçları ile ilgili bilgi durumları ve farkındalıkları

2019 ◽  
Vol 16 (2) ◽  
pp. 679-689 ◽  
Author(s):  
Süleyman Erhan Deveci ◽  
Osman Kurt ◽  
Edibe Pirinçci ◽  
Ayşe Ferdane Oğuzöncül
Keyword(s):  
Climate Change ◽  
Global Warming ◽  
Knowledge Score ◽  
Cross Sectional Study ◽  
Cross Sectional ◽  
Warming Climate ◽  
Level Of Knowledge ◽  
The Mean ◽  
High Level ◽  
Environmental Activities

This study was conducted to assess the knowledge and awareness of the students of the Faculty of Medicine on global warming, climate change and their consequences. In this Cross-sectional study a questionnaire was applied by reaching 404 persons from the Faculty of Medicine. The mean of knowledge points for global warming is 26.15 ± 2.88. The higher the grade, the lower the mean score (p=0.002), the higher the knowledge score of women (p=0.001). 4.5% of the students stated that they were a member of any environmental organization, 14.4% said they participated in environmental activities and 79.5% defended the necessity of environment related courses. As a result, it is found that the students of the Faculty of Medicine have a high level of knowledge of global warming. However, there is a lack of knowledge on the link between global warming and climate change and health problems and a lack of sensitivity to environmental activities. Education programs on global warming and climate change will be useful in the study group and other young groups.ÖzetBu çalışma Tıp Fakültesi Öğrencilerinin Küresel Isınma, İklim Değişikliği (KIİD) ve sonuçları konusundaki bilgi durumlarının ve farkındalıklarının değerlendirilmesi amacıyla yapılmıştır. Bu kesitsel çalışmada, Tıp Fakültesinden 404 kişiye ulaşılarak bir anket uygulanmıştır. Küresel ısınma bilgi puan ortalaması 26.15±2.88’dir. Sınıf yükseldikçe puan ortalamasının düştüğü (p=0.002), kadınların bilgi puanının daha fazla olduğu bulunmuştur (p=0.001). Öğrencilerin %4.5’i herhangi bir çevre kuruluşuna üyeliği olduğunu, %14.4’ü çevre ile ilgili aktivitelere katıldığını belirtmiş, %79.5’i ise çevre ile ilgili derslerin gerekliliğini savunmuştur. Sonuç olarak Tıp Fakültesi öğrencilerinin küresel ısınma ile ilgi bilgi düzeyleri yüksek bulunmuştur. Ancak KIİD ile sağlık sorunlarının ilişkilendirilmesi konusunda bilgi, yine çevre ile ilgili aktivitelere duyarlılık eksiklikleri mevcuttur. Bu araştırmanın yapıldığı çalışma grubu ve diğer genç gruplarda KIİD ile ilgili eğitim programları faydalı olacaktır.

Which regional cloud-radiative changes are most important for the global warming response of the midlatitude jet streams?

2020 ◽  
Author(s):  
Nicole Albern ◽  
Aiko Voigt ◽  
David W. J. Thompson ◽  
Joaquim G. Pinto
Keyword(s):  
Global Warming ◽  
Southern Hemisphere ◽  
Northern Hemisphere ◽  
North Atlantic ◽  
Radiative Heating ◽  
Jet Stream ◽  
Jet Streams ◽  
The North ◽  
The North Atlantic ◽  
The Impact

&lt;p&gt;Clouds and the midlatitude circulation are strongly coupled via radiation. Previous studies showed that global cloud-radiative changes contribute significantly to the global warming response of the midlatitude circulation. Here, we investigate the impact of regional cloud-radiative changes and identify which regional cloud-radiative changes are most important for the impact of global cloud-radiative changes. We show how tropical, midlatitude and polar cloud-radiative changes modify the annual-mean, wintertime and summertime jet stream response to global warming across ocean basins. To this end, we perform global simulations with the atmospheric component of the ICOsahedral Nonhydrostatic (ICON) model. We prescribe sea surface temperatures (SST) to isolate the impact of cloud-radiative changes via the atmospheric pathway, i.e. changes in atmospheric cloud-radiative heating, and mimic global warming by a uniform 4K SST increase. We apply the cloud-locking method to break the cloud-radiation-circulation coupling and to decompose the circulation response into contributions from cloud-radiative changes and from the SST increase.&lt;/p&gt;&lt;p&gt;In response to global warming, the North Atlantic, North Pacific, Northern Hemisphere and Southern Hemisphere jet streams shift poleward and the North Atlantic, Northern Hemisphere and Southern Hemisphere jets strengthen. Global cloud-radiative changes contribute to these jet responses in all ocean basins. &lt;span&gt;In the annual-mean and DJF, tropical and midlatitude cloud-radiative changes contribute significantly to the poleward jet shift in all ocean basins. &lt;/span&gt;&lt;span&gt;P&lt;/span&gt;&lt;span&gt;olar cloud-radiative changes shift the jet streams &lt;/span&gt;&lt;span&gt;poleward &lt;/span&gt;&lt;span&gt;in the northern hemispheric ocean basins &lt;/span&gt;&lt;span&gt;but&lt;/span&gt; &lt;span&gt;equatorward &lt;/span&gt;&lt;span&gt;in the Southern Hemisphere. In JJA, the poleward jet shift is small in all ocean basins. In contrast to the jet shift, the global cloud-radiative impacts on the 850hPa zonal wind and jet strength responses &lt;/span&gt;&lt;span&gt;result predominantly from &lt;/span&gt;&lt;span&gt;tropical cloud-radiative &lt;/span&gt;&lt;span&gt;changes&lt;/span&gt;&lt;span&gt;.&lt;/span&gt;&lt;/p&gt;&lt;p&gt;&lt;span&gt;The cloud-radiative impact on the jet shift can be related to changes in upper-tropospheric baroclinicity via increases in upper-tropospheric meridional temperature gradients, enhanced wave activity and increased eddy momentum fluxes. However, the response of the atmospheric temperature to cloud-radiative heating is &lt;/span&gt;&lt;span&gt;more difficult to understand because it is modulated by other small-scale processes such as convection and the circulation.&lt;/span&gt;&lt;span&gt; Our results help to understand the jet stream response to global warming and highlight the importance of regional cloud-radiative changes for this response, &lt;/span&gt;&lt;span&gt;in particular those in the tropics&lt;/span&gt;&lt;span&gt;.&lt;/span&gt;&lt;/p&gt;

Intensive and extensive movements of feral camels in central Australia

2020 ◽  
Vol 42 (3) ◽  
pp. 195
Author(s):  
Cameron Ryan Wells ◽  
Mark Lethbridge
Keyword(s):  
Dromedary Camels ◽  
Movement Trajectories ◽  
Multi Scale ◽  
The North ◽  
Brownian Bridges ◽  
The Mean ◽  
Central Australia ◽  
Relationship Of ◽  
The Relationship ◽  
Simpson Desert

A better understanding of the movement of feral dromedary camels (Camelus dromedarius) in Australia would be useful for planning removal operations (harvest or culling), because the pattern and scale of camel movement relates to the period they reside in a given area, and thus the search effort, timing and frequency of removal operations. From our results, we suspect that the dune direction influences how camels move across central Australia; particularly effects like the north–south longitudinal dune systems in the Simpson Desert, which appeared to elongate camel movement in the same direction as the dunes. We called this movement anisotropy. Research suggests camel movement in Australia is not migratory but partially cyclic, with two distinctive movement patterns. Our study investigated this further by using satellite tracking data from 54 camels in central Australia, recorded between 2007 and 2016. The mean tracking period for each animal was 363.9 days (s.e.m.=44.1 days). We used a method labelled multi-scale partitioning to test for changes in movement behaviour and partitioned more localised intensive movements within utilisation areas, from larger-scale movement, called ranging. This involved analysing the proximity of movement trajectories to other nearby trajectories of the same animal over time. We also used Dynamic Brownian Bridges Movement Models, which consider the relationship of consecutive locations to determine the areas of utilisation. The mean utilisation area and duration of a camel (n=658 areas) was found to be 342.6km2 (s.e.m.=33.2km2) over 23.5 days (s.e.m.=1.6 days), and the mean ranging distance (n=611 ranging paths) was a 45.1km (s.e.m.=2.0km) path over 3.1 days (s.e.m.=0.1 days).

scholarly journals Drivers of uncertainty in future projections of Madden–Julian Oscillation teleconnections

2021 ◽  
Vol 2 (3) ◽  
pp. 653-673
Author(s):  
Andrea M. Jenney ◽  
David A. Randall ◽  
Elizabeth A. Barnes
Keyword(s):  
North America ◽  
North Pacific ◽  
Static Stability ◽  
Boreal Winter ◽  
Madden Julian Oscillation ◽  
Future Projections ◽  
The North ◽  
The Mean ◽  
The North Pacific ◽  
Mean State

Abstract. Teleconnections from the Madden–Julian Oscillation (MJO) are a key source of predictability of weather on the extended timescale of about 10–40 d. The MJO teleconnection is sensitive to a number of factors, including the mean dry static stability, the mean flow, and the propagation and intensity characteristics of the MJO, which are traditionally difficult to separate across models. Each of these factors may evolve in response to increasing greenhouse gas emissions, which will impact MJO teleconnections and potentially impact predictability on extended timescales. Current state-of-the-art climate models do not agree on how MJO teleconnections over central and eastern North America will change in a future climate. Here, we use results from the Coupled Model Intercomparison Project Phase 6 (CMIP6) historical and SSP585 experiments in concert with a linear baroclinic model (LBM) to separate and investigate alternate mechanisms explaining why and how boreal winter (January) MJO teleconnections over the North Pacific and North America may change in a future climate and to identify key sources of inter-model uncertainty. LBM simulations suggest that a weakening teleconnection due to increases in tropical dry static stability alone is robust across CMIP6 models and that uncertainty in mean state winds is a key driver of uncertainty in future MJO teleconnections. Uncertainty in future changes to the MJO's intensity, eastward propagation speed, zonal wavenumber, and eastward propagation extent are other important sources of uncertainty in future MJO teleconnections. We find no systematic relationship between future changes in the Rossby wave source and the MJO teleconnection or between changes to the zonal wind or stationary Rossby wave number and the MJO teleconnection over the North Pacific and North America. LBM simulations suggest a reduction of the boreal winter MJO teleconnection over the North Pacific and an uncertain change over North America, with large spread over both regions that lends to weak confidence in the overall outlook. While quantitatively determining the relative importance of MJO versus mean state uncertainties in determining future teleconnections remains a challenge, the LBM simulations suggest that uncertainty in the mean state winds is a larger contributor to the uncertainty in future projections of the MJO teleconnection than the MJO.

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