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How can download the precipitation data from INDIAN METEOROLOGICAL DEPARTMENT(IMD) or Centre for Climate Change Research (CCCR) of Indian Institute of Tropical Meteorology
(IITM), Pune.
Could you refer to any other web sites?
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Check this link: https://www.ecmwf.int/
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The Madden-Julian Oscillation (MJO) event occurring earlier this year (2015) was said to be the strongest ever, based on its RMM index. I wonder if there is anyone ranking all the MJO events based on whatever criteria (e.g. RMM index, precipitation).
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As I know there is no historical ranking because (1) MJO discovered in 70s (2) still there is no universal accepted theory of MJO (3) reproduction of MJO by most GCM models is not doable.
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For predicting the future temperature in the Indian Himalayan Region, using IITM Cordex data or Worldclim (~1km Res) will be appropriate ?
IITM  - Indian Institute of Tropical Meteorology 
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CORDEX outputs is at 50km spatial resolution (0.44degrees)
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Hi, is there any published paper that mentioned westerlies (pressure belt between 30 to 60 degree North latitude) shift south during the colder period and shift north during warmer (summer period).
One more paper that shows the Intertropical Convergence zone (ITCZ) during summer and winter in the Indian subcontinent.  
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Dear Prabhat chandra Neupane,
See Figures 7.7 and 7.8 (Chapter 7: Scale of the Atmospheric Circulations) in the book below.
Regards,
Milivoj B. Gavrilov
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Generally we know the precipitation increases as altitude increases and along the orography of the mountains also. How do you calculate this gradient in precipitation?
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Please be concentrated towards remote sensing data for precipitation measurement in a mountain belt latitudinal and longitudinal to reach the conclusion.
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I am looking for the accurate location changes of ITCZ during the last 30 or 50 years. Have anyone done this work? Can you give some references?
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Could you please suggest a bibliographic reference about it?
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The atmospheric Hadley cells are the most stable part of the circulation system; at the surface they are the trade winds. They extend from ca. 5 to 25 N and S. You can make maps showing the plate tectonic evolution of the Caribbean at www.odsn.de/odsn/services/paleomap/paleomap.html
The paper with the plate tectonic details is Hay & Wold 1996 on my Researchgate site. Cretaceous climate model simulations sometimes produce 'supercanes'. Our first modern ones happened in 2005: see
Bill Hay
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We are performing nested runs with the WRF model to simulate weather over the equatorial Andes in South America. We are comparing model results against surface observations and sounding data. Since the WRF model works well for mid-latitude dynamics with the default options, I was wondering if it actually applies the right dynamics for equatorial regions. I am not sure if we are getting the right answers for the wrong reasons when we get good comparisons between the model and the observations.
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Hi Cazorla,
You have mentioned that your domain is  over the equatorial Andes in South America, which has  very complex topographic distribution. I do not know how big is your domain and at what resolution you are planning to run WRF and how many nest? 
WRF model's physical parameterization depends on the all the above above factors. If you look at available literature on WRF models sensitivity analysis then you will see that nearly all study concluded their papers as saying that do not choose physical parameterization combinations based on other study as WRF results depends on season, study location, variables of interest, domain size, length of simulation.
In my PhD research, I have done a comprehensive sensitivity analysis of WRF model over Canada and find that WRF results are sensitive to the above listed factors. 
Nevertheless, you will not find any other places which has steep mountain (Andes) and very cold ocean (East pacific). So, I would suggest you to do a small ensemble sensitivity experiment over your domain if you have computing resources and time.
Last but not least, I would strongly suggest you not to follow blindly other peoples selections. 
I hope that helps.
Thanks
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El-Nino, La-Nina, ENSO, Trend, Return Period
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Hi Muhammad, 
The appropriate representation of  "El Nino" is ENSO (El Nino Southern Oscillation). The "El Nino" only represents the Oceanic component and the Southern Oscillation indicates the Atmospheric component. Hence the name ENSO. In the atmospheric science community people use multiple indexes to define ENSO. The El Nino is defined as an increase of Eastern Tropical Pacific's sea surface temperature (SST) of 0.5 degree C from long term average (normally 30 years). And the La Nina is defined as a decrease of SST over the same area by -0.5 degree C from long term average.        
The ENSO has a recurrence interval of 2 to 7 years. You can use multiple tools to compute the return period or recurrence interval. I had used the Wavelet analysis tool to calculate amplitude and frequency of ENSO event in one of my graduate level course project.   
Beside the above link that Dr. Kenneth given, I would like to suggest you to visit the following web link for a series of articles on ENSO including different ENSO indexes; role of ENSO to global weather and climate  by renown atmospheric scientist professor Anthony G. Barnston's of Columbia University.  
Multivariate ENSO Index (MEI)
Why are there so many ENSO indexes, instead of just one?
Hope the above link will help you to find your answer more broadly 
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To group literature data into semi-humid and humid tropical, I want to use the Coefficient of Variation for monthly precipitation (data source: worldclim). From which CV on, sites can be seen as semi-humid / humid?
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Thanks Leonardo!
I'm just collecting basic climate data for a interpretation of some literature data. I recieved the climate data already (via worldclim). My question focuses on the interpretation of the data. 
I need a simple parameter to express the seasonality of precipitation to devide the literature sites into semi-humid and humid tropical. The Coefficient of Variation of the monthly rainfall (over several years) seams to be a possible way to express seasonality in my opinion. But from which CV on a site is called semi-humid?
Let's talk about the SC-parameterization soon. I trying to get access to a really nice dataset of SC-field data here from Goiania. I will get back to you when I get it.
Best wishes,
Dennis
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I have an interesting question.  If we remove the Northern Hemisphere Ice-sheet Or the Antarctic Ice-sheet expansion, will the ITCZ shift to north? Are there some related articels ? Thank you very much!
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The general thinking is that the ITCZ / Hadley circulation shifts toward the warmer hemisphere; this is in line with the seasonal variation as noted in Vadym's answer. A number of recent studies have shown evidence that extratropical heating anomalies have an impact on the tropical precipitation, particularly by affecting the position of the ITCZ. Examples:
Hwang, Y.-T., Frierson, D. M. W. and S. M. Kang. Anthropogenic sulfate aerosol and the southward shift of tropical precipitation in the 20th century. Geophys. Res. Lett., 40, 1-6, doi: 10.1002/grl50502, 2013.
Ceppi, P., Hwang, Y.-T., Liu, X., Frierson, D. M. W. and D. L. Hartmann. The relationship between the ITCZ and the Southern Hemisphere eddy-driven jet. J. Geophys. Res.-Atmospheres, 118, 5136-5146, doi: 10.1002/jgrd.50461, 2013.
What becomes apparent as you dive into this topic is that it isn't really the details of the energy source that matter. That is to say, it isn't the ice that matters in your example, or the sulfate aerosol in Hwang et al. Instead is the impact on the global energy cycle. 
Realizing that it is the global energy cycle that matters in these issues then brings the whole thing back to trying to understand fundamental aspects of the circulation. On this topic, there are a few recent studies that have noted that the impact on tropical precipitation of these high-latitude effects may depend on the representation of the ocean. In particular, a number of studies that show these tropical effects from extratropical forcing use only a thermodynamic ocean. Sometimes introducing a fully dynamic ocean model allows the oceanic response to adjust cooperatively with the atmosphere, and the tropical impact is substantially reduced. Two examples that show this pretty explicitly are:
Tomas, R. A, C. Deser and L. Sun, 2015: The role of ocean heat transport in the global climate response to projected Arctic sea ice loss. J. Climate, submitted. [preprint from Clara's web page: http://www.cgd.ucar.edu/staff/cdeser/docs/submitted.tomas.ocean_heat_transport_arctic.sep15.pdf]
Kay, J. E., Yettella, V., Medeiros, B. Hannay, C., and P. Caldwell (revised), Global climate impacts of fixing the Southern Ocean shortwave radiation bias in the Community Earth System Model, J. Climate, [preprint from Jen's web page: http://www.cgd.ucar.edu/staff/jenkay/papers/Kay_JClim_SouthernOceanASR_revised_November2,2015.pdf]
Hope that is helpful.
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I've got some wind speed measurements and I would like to find out which test is the most reasonable one to clarify if the data is stationary or not. Your help is highly appreciated.
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Hi Thomas,
I am not sure if you already have a satisfactory answer, but I would like to provide an answer anyway. First of all, I am glad to see that researchers/engineers across the world are still on a look out for a robust method to identify stationarity in wind speed time series. It gives me some comfort that I am not alone in this. 
After parsing through the literature in the past, one of the better methods that I could think of is from Andreas et.al. (2008). It somehow takes care of correlations on a very short time scale, which I believe they do by estimating the integral time scale. Please find the details in this publication.
In case you have found a new/better method then I am very interested to know that too. 
Kind Regards,
Ameya
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The Safir-Simpson hurricane scale is a classification method to identify the intensity of a tropical cyclone by civil engineer Herbert Saffir and meteorologist Bob (Robert) Simpson, but this method proved to be useless due to its failures to identify the two thirds of the top 156 deadliest hurricanes from 1851 to 1996. I found the overgeneralization problem caused this.
I developed a new classification method to deal with this problem, but many reviewers and editors told me that even though what you said is correct, we still insist on using SSHS, and your paper can't be published at least in the journals of USA due to common people accepting SSHS. I really don't know why this thing could happen in scientific world, any people know the true reason?
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one year ago , I found it , and downlaod from the official weasite. But I don't know why they disaperar recently, if you want , I would forward the data which I download one year ago.
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In the response of my last question related to Saffir-simpson Hurricane Scale(SSHS), some people claimed that "Stronger TCs usually have stronger winds but do not always have stronger damage to human and vice versa." I think that he doesn't know OGP problems of SSHS. SSHS use the maximum sustaining winds to stand for the intensity of a tropical cyclone, so there is an overgeneralization problem(OGP), due to the area of the maximum sustaining winds  is just very small part of whole area of a tropical cyclone.  For example, a person has a big head, but his body is very short, we can not say the man is very strong man. That is the OGP problem!!
     Is it funny that some people didn't know this and made a wrong conclusion to
comment on a new classification method for tropical cyclones?
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 In science, if we want to investigate any scientific problem, major influence factors should be given more priority to be investigated. However, only one field is an exception: that is global climate warming. Many scientists ignore the major climate influence factors and consider greenhouse effect  due to human reasons to be the main reason , although they knew it is much smaller than the major climate factors.
     Their logic is that the recent unusual trend of land surface temperature is non-periodic, major periodic factors only cause periodic changes.
     Recently, after more than a half year's effort, we prove that the monthly anomaly of global land surface temperature can be fitted perfectly by a group of periodic functions, the verification results indicate that the correlated coefficients of more than 15,000 periodic functions are all more than 0.9.(Last year, I mentioned I found a function which its the correlated coefficient is 0.8)
    I send the paper to one of the toppest IF magazines, the editor said" we know  your reseach result is absolutely right,but many people already believe in this view, thousands of papers have already published , so we have to reject your paper. And we also tell you that  no magazine is willing to publish your paper".
    One anonymous email is send to me with the following word :
         "Birth is much, but breeding is more."
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Such as the wind speed,precipitation,temperature,air pressure,and relative humidity.
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In Mexico you would have to log into the National Meteorological Service web page and choose de automatic weather station option. Most of this stations measure every 10 min and report measurements either every hour or every 3 hours. You would have de choice of data for last 24 h @ 10 min, or last 7 days @ 60 min or last 90 days @ 24 h.
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Paterson's Climate Vegetation Productivity (CVP) index is used to quantify potential forest productivity of any region using meteorological factors.
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You could ask Frank Wadsworth and John Parrotta in the US Forest Service, both of whom were familiar with Holdridge and his original classification. - JB
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There are models for the structure of hurricane winds (e.g. Holland, 1980, Holland et al., 2010) which are typically applied at the the sea surface for studies of air-sea interaction. We know that in the surface boundary layer, under neutral conditions, Monin-Obikov theory may be applied to find the wind speed as a function of altitude and this is an exponential curve (so called "law of the wall"). Is there any reason that the wind direction might also be a function of altitude? Has the vertical profile of wind direction in a hurricane ever been measured (at a stationary point in the hurricane reference frame)?
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I have to respectfully disagree with Alastair McDonald's reply.  The upper air away from the surface does of course follow the cylindrical circulation (so long as you are still low in the atmosphere).  But the question is about wind close to the surface, which is governed not only by the pressure gradient and coriolis effects of the upper air, but also frictional effects from the surface.
The Eckman calculation is single column, and is indifferent to the large scale circulation.  In a low pressure system you see the effects as air near the ground cuts across the pressure contours at nearly 45 degrees, but upper air follows the pressure contours.  A hurricane is just a massive low pressure system.  The Eckman profile holds at each location, so that the wind near the ground inclines towards the local low pressure (not directly towards it) while higher  air will circulate perpendicular to the pressure.  Higher still the wind becomes vertical, then eventually switches to circulating the opposite direction.  But all this higher stuff is not Eckman circulation, and does not pertain to the question about surface winds.  About a km high the air is moving around the local low pressure; below it begins to turn so that near the ground it has a component towards the low pressure.
Over ocean, the friction is low ccmpared to land, so near the surface the wind will be closer to circulating around the low pressure than over land, but will still have a component towards the low pressure.
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Is there any open source software allowing me to download TRMM data?
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In my knowledge TRMM do not provide hourly data. The maximum temporal resolution is 3 hourly for trmm but there are some other RS data like CMORPH (ftp://ftp.cpc.ncep.noaa.gov/precip/CMORPH_V1.0/RAW/) which also has 30 minutes temporal resolution but the spatial resolution is coarser (2.5deg) and I think this data is not recommended for tropical region.
the ftp link to download netcdf files of TRMM data is (3 hourly, daily and monthly mean)
the other link to download TRMM data is (Here you can download the TRMM data in other file formats also)
I hope this gives you the answer.
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 When do the intertropical convergence zone (ITCZ) move southward during climate change for the northern hemisphere?
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Dear Wancan
I do agree with Fabrice Lambert response. The seasonal ITCZ shift is a regional process. It is associated with the seasonal differential warming between the continent and the ocean. The problem you pose is interesting in case of global warming, as both continental and oceanic warmings may exist. So the question is how this differential Continent/ocean warming may evolve. I have not the solution but you may find some consideration on the coupling between the ocean and atmospheric monsoon in a peper I recently published with csome considerations of the variability of the coupling. You can find the paper on my reaserch gate site.
Regards
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I need  Tdb and RH% or Tdb and Twb and mostly important : solar intensity . I need them for the purpose of estimating a whole year energy consumption for a new air conditioning system configuration. I wish to find a source for this information in the form of excel sheet table or similar. 
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The book:
Solar Engineering of Thermal Processes, 4th Edition
Gives a lot of information specially in appendix for solar simulation. There are many formula for sun directions and so on.
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I have been observing that when monsoon moisture moves over certain tropical forests located in SE Asia or India, rain clouds with very long streaks form.  Has anyone studied if this is caused by Pseudomonas bacteria that live on particular species of tropical trees, and if so which tree species produce the most rain clouds?  Attached is a satellite image from August 2014 showing these particular clouds forming over the forests along the SW coast of India.
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Pseudomonas type of bacteria species  is a common ice nuclei (IN) positive bacteria found among many other bacteria in clouds. There are several findnings on Pseudomonas syringae over the globe.  In India, we have collected Pseudomonas aeruginosa from Northern part of India and tested the ice nucleating characteristics of this particular bacteria over Indian subcontinent.
Bio-aerosol like bacteria can be nucleated at higher temperature and lower super saturation value that may helps to initiate cloud glaciations more quickly in terms of precipitation.
see "Study of ice nucleating characteristics of Pseudomonas aeruginosa” A. Hazra, M. Saha, U. K. De, J. Mukherjee and K. Goswami,; Journal of Aerosols Science, vol, 35, pp 1405-1414, 2004."
see "“Parameterizing ice nucleation rates using Contact Angle and Activation Energy Derived from Laboratory Data” by J-P Chen  A. Hazra, Z. Levin, Atmospheric Chemistry and Physics, 8, 7431-7449, 2008."
see "“A classical-theory-based parameterization of heterogeneous ice nucleation by mineral dust, soot and biological particles in a global climate model”, Hoose, C.,J. E. Kristjánsson, J.-P. Chen and A. Hazra (2010): Journal of Atmospheric Sciences, 67, 2483-2503."