seyyedalireza
مدیر موقت
اگه نقشه هارو ول کنیم میتونیم از هواشناسی تجربیات هم استفاده کنیم. از اساتید خواستارم که بنظرشون چه نوع بارش ما داریم و از تجربه شون استفاده کنن و بگن
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توجه: در صورتی که از کاربران قدیمی ایران انجمن هستید و امکان ورود به سایت را ندارید، میتوانید با آیدی altin_admin@ در تلگرام تماس حاصل نمایید.
تجزیه و تحلیل وضعیت جوی در سال زراعی 93-94 /فصل دوم( دي- بهمن-اسفند)
- شروع کننده موضوع heaven1
- تاریخ شروع
- وضعیت
ali_kermanshah
کاربر ويژه
Gfs دوباره سرما و بارش سواحل را كمي زياد كرد
Amir Mohsen
متخصص بخش هواشناسی
Global
The average global temperature anomaly for combined land and ocean surfaces during December 2005 (based on preliminary data) was 0.70°F (0.39°C) above the 1880-2004 long-term mean. This was the 9th warmest December since 1880 (the beginning of reliable instrumental records), and the annual global surface temperature was near the record established in 1998. Although land surface temperatures in December were anomalously warm across Alaska, West Africa and parts of the Middle East and western Russia, cooler-than-average conditions were widespread across south-central Russia, the eastern U.S., and southern Europe. Neutral El Niño/Southern Oscillation conditions continued in the equatorial Pacific, although indications that a weak La Niña episode may develop in 2006 were highlighted by anomalously cold sea surface temperatures in the eastern equatorial Pacific.
The average global temperature anomaly for combined land and ocean surfaces during December 2005 (based on preliminary data) was 0.70°F (0.39°C) above the 1880-2004 long-term mean. This was the 9th warmest December since 1880 (the beginning of reliable instrumental records), and the annual global surface temperature was near the record established in 1998. Although land surface temperatures in December were anomalously warm across Alaska, West Africa and parts of the Middle East and western Russia, cooler-than-average conditions were widespread across south-central Russia, the eastern U.S., and southern Europe. Neutral El Niño/Southern Oscillation conditions continued in the equatorial Pacific, although indications that a weak La Niña episode may develop in 2006 were highlighted by anomalously cold sea surface temperatures in the eastern equatorial Pacific.
seyyedalireza
مدیر موقت
طبق نقشه های چی اف اس باز مثل سال پیش شمال شرق ایران صفرا با شش و زمانی که سامانه از ایران بیرون می ره بارش عاليي در افقانستان داره
من که از وقتی جی اف اس و به خصوص ای سی ام بارشامونو به شدت کم کردم بر خلاف بعضی از دوستان که خوشحال هم میشدن احتمال بارش برف خوب رو بعید دیدم مگه میشه اخه ای سی ام سه چهار میل به زور بارون و برف پیشبینی کرده باشه و یکدفعه سی سانت برف بیاد...خودمونوکه نمیخوایم گول بزنیم..
ali_kermanshah
کاربر ويژه
در آپديت جديد اكيو ودر به گرد و خاك اشاره شده كه در اين تصوير هم مشخصه ( رنگ صورتي )
واسه ما که بزور 540 قدم رنجه. میکنن
واقعا بعضی هاخیلی بی انصاف تشریف دارن یا تو رویا بسر می برن سیستم دهه ۵۰ و سال ۸۶ کجا این سیستم کجا ۰۰۰ بابا خدایش تازه با ورود این سیستم دوباره به نرمال زمستون برمیگردیم نا سلامتی زمستونه اگه هوا سرد نشه پس کی میخواد سرد بشه ۰۰۰
بارش این سیستم بجز شمال کشور در حد خیس شدن زمینها هم نیست ۰۰۰ سرمای هوا هم فقط موجبات خنده میشه و بس ۰۰۰ دمای ۲۳ درجه زیر صفر مشهد کجا ، دمای ۱۵- تهران ، ۳۴- همدان و ۰۰۰۰
بارش این سیستم بجز شمال کشور در حد خیس شدن زمینها هم نیست ۰۰۰ سرمای هوا هم فقط موجبات خنده میشه و بس ۰۰۰ دمای ۲۳ درجه زیر صفر مشهد کجا ، دمای ۱۵- تهران ، ۳۴- همدان و ۰۰۰۰
یک جورائی از مطالب دوستان و سایتها این نتیجه رو می توان گرفت که سیستم که در حال ورود به ایران است از لحاظ کارکرد و ساختارش بسیار خوب است می ماند شرایط تغذیه رطوبتی آن
خلیج فارس و دریای سرخ و اقیانوس هند که رطوبت دهی خوبی ندارند می ماند مدیترانه و دریای سیاه و خزر که رطوبت دهی آنها می تواند در مناطق غربی بهتر باشد
در مناطق شرقی شرایط خیلی پیچیده تر است آیا طوبت رسانی خوب صورت می گیرد یا مناطق به صورت نقطه ای بارشهای خوبی خواهند داشت؟
خلیج فارس و دریای سرخ و اقیانوس هند که رطوبت دهی خوبی ندارند می ماند مدیترانه و دریای سیاه و خزر که رطوبت دهی آنها می تواند در مناطق غربی بهتر باشد
در مناطق شرقی شرایط خیلی پیچیده تر است آیا طوبت رسانی خوب صورت می گیرد یا مناطق به صورت نقطه ای بارشهای خوبی خواهند داشت؟
Amir Mohsen
متخصص بخش هواشناسی
اگر که MJO در فاز مناسب قرار داشت!!!!!!!!!
صبح فردا:
صبح فردا:
Amir Mohsen
متخصص بخش هواشناسی
وحید - مشهد
کاربر ويژه
دوست عزیز دریای سیاه و دریای خزر نقشی در مناطق غربی ندارن(فقط دریای سیاه در شمال غرب موثره) .بر عکس در صورت گسیل رطوبت از سوی ابن دو دریا شرایط ایده ال در شمال و شمال شرق خواهیم داشت
دریای مدیترانه هم که تکلیفش مشخصه .نسبت من با این دریا مثه کارد و پنیره!!!!!!!!!!!!
وحید - مشهد
کاربر ويژه
پس داره صعودی میشه..
Amir Mohsen
متخصص بخش هواشناسی
[h=2]What is the MJO, and why do we care?
Author:
Jon Gottschalck
Wednesday, December 31, 2014
The articles posted on this blog have described ENSO, its regional and global impacts, and the challenge of forecasting it, among several other topics. Here we introduce another important player on the tropical stage: the Madden-Julian Oscillation, or MJO. While the MJO is a lesser-known phenomenon, it can have dramatic impacts in the mid-latitudes. Several times a year the MJO is a strong contributor to various extreme events in the United States, including Arctic air outbreaks during the winter months across the central and eastern portions of the United States.
[h=3]So what is the MJO? Imagine ENSO as a person riding a stationary exercise bike in the middle of a stage all day long. His unchanging location is associated with the persistent changes in tropical rainfall and winds that we have previously described as being linked to ENSO. Now imagine another bike rider entering the stage on the left and pedaling slowly across the stage, passing the stationary bike (ENSO), and exiting the stage at the right. This bike rider we will call the MJO and he/she may cross the stage from left to right several times during the show.
So, unlike ENSO, which is stationary, the MJO is an eastward moving disturbance of clouds, rainfall, winds, and pressure that traverses the planet in the tropics and returns to its initial starting point in 30 to 60 days, on average. This atmospheric disturbance is distinct from ENSO, which once established, is associated with persistent features that last several seasons or longer over the Pacific Ocean basin. There can be multiple MJO events within a season, and so the MJO is best described as intraseasonal tropical climate variability (i.e. varies on a week-to-week basis).
The MJO was first discovered in the early 1970s by Dr. Roland Madden and Dr. Paul Julian when they were studying tropical wind and pressure patterns. They often noticed regular oscillations in winds (as defined from departures from average) between Singapore and Canton Island in the west central equatorial Pacific (Madden and Julian, 1971; 1972; Zhang, 2005).
The MJO consists of two parts, or phases: one is the enhanced rainfall (or convective) phase and the other is the suppressed rainfall phase. Strong MJO activity often dissects the planet into halves: one half within the enhanced convective phase and the other half in the suppressed convective phase. These two phases produce opposite changes in clouds and rainfall and this entire dipole (i.e., having two main opposing centers of action) propagates eastward. The location of the convective phases are often grouped into geographically based stages that climate scientists number 1-8 as shown in Figure 1.
Figure 1: Difference from average rainfall for all MJO events from 1979-2012 for November-March for the eight phases described in the text. The green shading denotes above-average rainfall, and the brown shading shows below-average rainfall. To first order, the green shading areas correspond to the extent of the enhanced convective phase of the MJO and the brown shading areas correspond to the extent of the suppressed convective phase of the MJO. Note eastward shifting of shaded areas with each successive numbered phase as you view the figure from top to bottom.
For the MJO to be considered active, this dipole of enhanced/suppressed convective phases must be present and shifting eastward with time. An animated illustration that depicts the global scale and eastward propagation of these two phases of the MJO is shown here (Fig. 2: animation).
Figure 2. An animation illustrating the organization of the MJO into its enhanced and suppressed convective phases during an MJO event during the spring of 2005. The green shading denotes conditions favorable for large-scale enhanced rainfall, and the brown shading shows conditions unfavorable for rainfall. The MJO becomes organized during late March through May as the green shading covers one half of the planet, and brown shades the other half all along as these areas move west to east with time. Notice how the shading returns to the same location on the order of about 45 days.
[h=3]What’s behind the pattern? Let’s dig a little deeper and look at some of the characteristics within these two convective phases (Figure 3). In the enhanced convective phase, winds at the surface converge, and air is pushed up throughout the atmosphere. At the top of the atmosphere, the winds reverse (i.e., diverge). Such rising air motion in the atmosphere tends to increase condensation and rainfall.
Figure 3: The surface and upper-atmosphere structure of the MJO for a period when the enhanced convective phase (thunderstorm cloud) is centered across the Indian Ocean and the suppressed convective phase is centered over the west-central Pacific Ocean. Horizontal arrows pointing left represent wind departures from average that are easterly, and arrows pointing right represent wind departures from average that are westerly. The entire dipole shifts eastward over time, eventually circling the globe and returning to its point of origin. Climate.gov drawing by Fiona Martin.
In the suppressed convective phase, winds converge at the top of the atmosphere, forcing air to sink and, later, to diverge at the surface (Rui and Wang, 1990). As air sinks from high altitudes, it warms and dries, which suppresses rainfall.
It is this entire dipole structure, illustrated in Figure 3, that moves west to east with time in the Tropics, causing more cloudiness, rainfall, and even storminess in the enhanced convective phase, and more sunshine and dryness in the suppressed convective phase.
The changes in rainfall and winds described above impact both the Tropics and the Extratropics, which makes the MJO important for extended-range weather and climate prediction over the U.S. and many other areas. The MJO can modulate the timing and strength of monsoons (e.g., Jones and Carvalho, 2002; Lavender and Matthews, 2009), influence tropical cyclone numbers and strength in nearly all ocean basins (e.g., Maloney and Hartmann, 2000), and result in jet stream changes that can lead to cold air outbreaks, extreme heat events, and flooding rains over the United States and North America (Higgins et al. 2000, Cassou, 2008, Lin et al. 2009, Zhou et al., 2012, Riddle et al., 2013, Johnson et al., 2014).
The MJO can produce impacts similar to those of ENSO, but which appear only in weekly averages before changing, rather than persisting and therefore appearing in seasonal averages as is the case for ENSO.
Future posts will focus on the details of how we monitor and assess the strength of the MJO, provide details on impacts and the reasons for those impacts, and describe the current state of MJO predictability. Realtime MJO information that is updated daily or weekly can be found on the NOAA CPC MJO webpage.
Author:
Jon Gottschalck
Wednesday, December 31, 2014
The articles posted on this blog have described ENSO, its regional and global impacts, and the challenge of forecasting it, among several other topics. Here we introduce another important player on the tropical stage: the Madden-Julian Oscillation, or MJO. While the MJO is a lesser-known phenomenon, it can have dramatic impacts in the mid-latitudes. Several times a year the MJO is a strong contributor to various extreme events in the United States, including Arctic air outbreaks during the winter months across the central and eastern portions of the United States.
[h=3]So what is the MJO? Imagine ENSO as a person riding a stationary exercise bike in the middle of a stage all day long. His unchanging location is associated with the persistent changes in tropical rainfall and winds that we have previously described as being linked to ENSO. Now imagine another bike rider entering the stage on the left and pedaling slowly across the stage, passing the stationary bike (ENSO), and exiting the stage at the right. This bike rider we will call the MJO and he/she may cross the stage from left to right several times during the show.
So, unlike ENSO, which is stationary, the MJO is an eastward moving disturbance of clouds, rainfall, winds, and pressure that traverses the planet in the tropics and returns to its initial starting point in 30 to 60 days, on average. This atmospheric disturbance is distinct from ENSO, which once established, is associated with persistent features that last several seasons or longer over the Pacific Ocean basin. There can be multiple MJO events within a season, and so the MJO is best described as intraseasonal tropical climate variability (i.e. varies on a week-to-week basis).
The MJO was first discovered in the early 1970s by Dr. Roland Madden and Dr. Paul Julian when they were studying tropical wind and pressure patterns. They often noticed regular oscillations in winds (as defined from departures from average) between Singapore and Canton Island in the west central equatorial Pacific (Madden and Julian, 1971; 1972; Zhang, 2005).
The MJO consists of two parts, or phases: one is the enhanced rainfall (or convective) phase and the other is the suppressed rainfall phase. Strong MJO activity often dissects the planet into halves: one half within the enhanced convective phase and the other half in the suppressed convective phase. These two phases produce opposite changes in clouds and rainfall and this entire dipole (i.e., having two main opposing centers of action) propagates eastward. The location of the convective phases are often grouped into geographically based stages that climate scientists number 1-8 as shown in Figure 1.
For the MJO to be considered active, this dipole of enhanced/suppressed convective phases must be present and shifting eastward with time. An animated illustration that depicts the global scale and eastward propagation of these two phases of the MJO is shown here (Fig. 2: animation).
[h=3]What’s behind the pattern? Let’s dig a little deeper and look at some of the characteristics within these two convective phases (Figure 3). In the enhanced convective phase, winds at the surface converge, and air is pushed up throughout the atmosphere. At the top of the atmosphere, the winds reverse (i.e., diverge). Such rising air motion in the atmosphere tends to increase condensation and rainfall.
Figure 3: The surface and upper-atmosphere structure of the MJO for a period when the enhanced convective phase (thunderstorm cloud) is centered across the Indian Ocean and the suppressed convective phase is centered over the west-central Pacific Ocean. Horizontal arrows pointing left represent wind departures from average that are easterly, and arrows pointing right represent wind departures from average that are westerly. The entire dipole shifts eastward over time, eventually circling the globe and returning to its point of origin. Climate.gov drawing by Fiona Martin.In the suppressed convective phase, winds converge at the top of the atmosphere, forcing air to sink and, later, to diverge at the surface (Rui and Wang, 1990). As air sinks from high altitudes, it warms and dries, which suppresses rainfall.
It is this entire dipole structure, illustrated in Figure 3, that moves west to east with time in the Tropics, causing more cloudiness, rainfall, and even storminess in the enhanced convective phase, and more sunshine and dryness in the suppressed convective phase.
The changes in rainfall and winds described above impact both the Tropics and the Extratropics, which makes the MJO important for extended-range weather and climate prediction over the U.S. and many other areas. The MJO can modulate the timing and strength of monsoons (e.g., Jones and Carvalho, 2002; Lavender and Matthews, 2009), influence tropical cyclone numbers and strength in nearly all ocean basins (e.g., Maloney and Hartmann, 2000), and result in jet stream changes that can lead to cold air outbreaks, extreme heat events, and flooding rains over the United States and North America (Higgins et al. 2000, Cassou, 2008, Lin et al. 2009, Zhou et al., 2012, Riddle et al., 2013, Johnson et al., 2014).
The MJO can produce impacts similar to those of ENSO, but which appear only in weekly averages before changing, rather than persisting and therefore appearing in seasonal averages as is the case for ENSO.
Future posts will focus on the details of how we monitor and assess the strength of the MJO, provide details on impacts and the reasons for those impacts, and describe the current state of MJO predictability. Realtime MJO information that is updated daily or weekly can be found on the NOAA CPC MJO webpage.
سامان جان خصوصی ات رو چک کن
اگر آمریکا....اگه mjo در فاز 6 یا 7 بود تهران برف سنگین داشت. (با اجازه امیر محسن :خنده1
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