I found out that a bunch of the videos that I added to the COSEE website were actually being left out on purpose. Apparently a lot of websites flat out refuse to let us upload anything from their site. I'm slowly learning just how difficult it is to find quality educational images and videos that we are at the same time also available for us to use.
Today I worked on Jennifer's and my idea to upload short sample videos downloaded using a screen capture program when the video can't be normally downloaded. This allows the person looking at the site to see what the video is like and then click the external link to see the full version with sound and better quality.
I also had the idea to use hyperlinks to the source websites more often even with things like images so that the user can gain more information about a topic and so we don't have to cram a 1000 lines in to the description window.
I found out that the text boxes for the descriptions do not accept foreign characters so every time I tried to say El Niño it ended up saying El Nio.
A few days ago I used my new found MatLab skills to make a graph of some information I found concerning hurricanes and El Niño.
Wednesday, July 22, 2009
Wednesday, July 8, 2009
Finishing Looking at Seasonal Peak Chlorophyll and Starting With SST Data
I plotted the residual chlorophyll concentrations at the times of the primary and secondary chlorophyll bloom peaks. This was to double check if there were any significant trends in seasonal peak chlorophyll concentrations. Using the the residual chlorophyll concentrations did not show any significant overall trends though.
I also went back and changed the dates that I used when comparing the day of year that a bloom started. I changed it from the dates of the highest concentration in that seasonal bloom to the date that the bloom first started to increase. My thinking was that the date of the peak wasn't as important since the peak tended to occur at several different stages of the bloom. I felt that the triggering of the start of the bloom was instead what we were looking to for signs of a trend. However this again did not show any significant trend leading to a possible conclusion that the start times of the blooms are not getting significantly earlier or later year to year.
Yesterday I started working with the sea surface temperature data. This required gaining an understanding of netcdf files and how to use them. Once I had the right MATLAB files downloaded I started going through Carrie's preexisting code to try to clean it up a little and make it more open to possible changes to the dates we choose to analyze. Also I downloaded the land sea mask and took a while to write a code that could use it.
Today I continued cleaning up the code a little bit and looked into getting the right dates to show up. NOAA uses the same serial date format as MATLAB only it starts in 1800 instead of starting at 0 A.D. The simplest way I found of fixing this was to just add 657,436, the equivalent of 1800 years, to all the time data points when first loading them in. I double checked this and found it left the day and month unchanged but now all the years are correct displaying 1981 instead of 181.
I also went back and changed the dates that I used when comparing the day of year that a bloom started. I changed it from the dates of the highest concentration in that seasonal bloom to the date that the bloom first started to increase. My thinking was that the date of the peak wasn't as important since the peak tended to occur at several different stages of the bloom. I felt that the triggering of the start of the bloom was instead what we were looking to for signs of a trend. However this again did not show any significant trend leading to a possible conclusion that the start times of the blooms are not getting significantly earlier or later year to year.
Yesterday I started working with the sea surface temperature data. This required gaining an understanding of netcdf files and how to use them. Once I had the right MATLAB files downloaded I started going through Carrie's preexisting code to try to clean it up a little and make it more open to possible changes to the dates we choose to analyze. Also I downloaded the land sea mask and took a while to write a code that could use it.
Today I continued cleaning up the code a little bit and looked into getting the right dates to show up. NOAA uses the same serial date format as MATLAB only it starts in 1800 instead of starting at 0 A.D. The simplest way I found of fixing this was to just add 657,436, the equivalent of 1800 years, to all the time data points when first loading them in. I double checked this and found it left the day and month unchanged but now all the years are correct displaying 1981 instead of 181.
Thursday, July 2, 2009
Working With COSEE Stuff
So far in my COSEE job I have learned a lot. Just the process of downloading all the right software I needed took a great deal of time and learning. I've been learning about how to convert video files from one form to another, how to capture videos from the screen, and how to edit these videos. I found that many of the videos already on the website were not working so the main thing I've put time into has been trying to get all the videos that were already uploaded to actually run.
Yesterday I finished fixing all of the already active videos and started looking for some actual new content. One thing I want to focus on is trying to find meaningful pictures and videos that will actually help someone to teach or learn the basic concepts. Alot of the pictures and videos that I have come across are too scientific and detailed to be useful to someone not already educated in the subject. On the other hand some of the pictures and videos are just fun or interesting to look at without containing much educational content at all. It is going to be difficult to balance between these two extremes.
Yesterday I finished fixing all of the already active videos and started looking for some actual new content. One thing I want to focus on is trying to find meaningful pictures and videos that will actually help someone to teach or learn the basic concepts. Alot of the pictures and videos that I have come across are too scientific and detailed to be useful to someone not already educated in the subject. On the other hand some of the pictures and videos are just fun or interesting to look at without containing much educational content at all. It is going to be difficult to balance between these two extremes.
Working With Residual Chlorophyll and Chlorophyll Peaks
Yesterday I reworked my monthly chlorophyll program to find and work with the residual chlorophyll data. I got some good practice making two different "for" loops in the program. One found the mean chlorophyll concentration of each month and the other found the difference between each chlorophyll concentration and their respected monthly average. I learned a lot about how useful loops like this can be to save time in the future.
Today I was working with the peak chlorophyll concentrations again. I was trying to answer whether the main and/or secondary concentration peaks were increasing with time. I found out how to use the data cursor in the plot tools to select multiple points at once and export their coordinates to a struct in the workspace. After I figured out how to call a piece of data in a struct I made another "for" loop to put the data points into a matrix that I could then run the "regress" function on.
I also tried to answer whether the main and/or secondary peaks in chlorophyll concentration were coming later or sooner in the season each year. I did this by finding the serial date numbers of January first for all the years between 1997 and 2008. Then I subtracted these numbers from each peaks original serial date number to get the number of days into the year that each of the peaks were occurring. So far neither the day of the year the peaks occur or the concentration at the peaks have given significant trends. For the rest of the day I'm going to rerun the programs using residual data to see if that makes a difference.
Today I was working with the peak chlorophyll concentrations again. I was trying to answer whether the main and/or secondary concentration peaks were increasing with time. I found out how to use the data cursor in the plot tools to select multiple points at once and export their coordinates to a struct in the workspace. After I figured out how to call a piece of data in a struct I made another "for" loop to put the data points into a matrix that I could then run the "regress" function on.
I also tried to answer whether the main and/or secondary peaks in chlorophyll concentration were coming later or sooner in the season each year. I did this by finding the serial date numbers of January first for all the years between 1997 and 2008. Then I subtracted these numbers from each peaks original serial date number to get the number of days into the year that each of the peaks were occurring. So far neither the day of the year the peaks occur or the concentration at the peaks have given significant trends. For the rest of the day I'm going to rerun the programs using residual data to see if that makes a difference.
Monday, June 29, 2009
MATLAB Work
In order to understand how to better use MATLAB I carefully went through Carrie's code used for her original analysis. As I went through I tried to make sure I understood what every function and calculation was used for. After gaining a solid foundation in using the basic functions of MATLAB I began going over Professor Xue's SMS 595 lecture notes.
I worked through the first two lectures making sure I knew the basics of linear regression and understood how to interpret the results Carrie and I would be seeing. In order to better understand the regression function Carrie and I would be using in MATLAB I anaylzed a data set givien to Carrie in SMS 595 as homework. The funtion in MATLAB that Carrie and I are using gives several sets of statistics without clear definitions of their identities and purposes. Using Professor Xue's notes however I was able to match up the numbers given in MATLAB to the explanations in Professor Xue's notes and gain a better understanding of the "regress" function.
After that I began work on the time consuming yet useful task of reproducing Carrie's original regression results. Without looking at Carrie's code I used Professor Xue's notes and the Help files in MATLAB to write my own program to load, split, preform a regression on, and plot the 8-day Chlorophyll area averaged data. After my program for the 8-day data was finished it was short work to load and modify the monthly averaged data so it would run using mostly the same code.
I also began work on analyzing the extremes in the chlorophyll data. For quite some time I expirimented with ways of doing this in MATLAB since I couldn't find a specific premade function. I wrote a program that could be used to find the highest chlorophyll concentration between certain times that worked but ultimately I found to be a waste. By far the easiest way to find the extremes with this data is to just use the data cursor in the figure window to select the point at the peak in each season and make a matrix from the x and y values it gives you.
I worked through the first two lectures making sure I knew the basics of linear regression and understood how to interpret the results Carrie and I would be seeing. In order to better understand the regression function Carrie and I would be using in MATLAB I anaylzed a data set givien to Carrie in SMS 595 as homework. The funtion in MATLAB that Carrie and I are using gives several sets of statistics without clear definitions of their identities and purposes. Using Professor Xue's notes however I was able to match up the numbers given in MATLAB to the explanations in Professor Xue's notes and gain a better understanding of the "regress" function.
After that I began work on the time consuming yet useful task of reproducing Carrie's original regression results. Without looking at Carrie's code I used Professor Xue's notes and the Help files in MATLAB to write my own program to load, split, preform a regression on, and plot the 8-day Chlorophyll area averaged data. After my program for the 8-day data was finished it was short work to load and modify the monthly averaged data so it would run using mostly the same code.
I also began work on analyzing the extremes in the chlorophyll data. For quite some time I expirimented with ways of doing this in MATLAB since I couldn't find a specific premade function. I wrote a program that could be used to find the highest chlorophyll concentration between certain times that worked but ultimately I found to be a waste. By far the easiest way to find the extremes with this data is to just use the data cursor in the figure window to select the point at the peak in each season and make a matrix from the x and y values it gives you.
Thursday, June 18, 2009
The First Few Days
Everything so far has been mainly focused on getting setup and prepared for the coming weeks. The first day I setup the computer that I'm going to be using and began the long and surprisingly complicated process of downloading and installing the latest version of MATLAB. Also I needed to complete all of my safety training both online and in person with Tim.
The second day I spent more time trying to download and install MATLAB and Carrie gave me a more detailed run-through of her project for Professor Xue's class and her results so far.
Wednesday Carrie was gone so I didn't come in.
Today I have spent the better part of the morning going through MATLAB tutorials and trying to get up to speed with how the program works. Carrie is going to give me some of the data she used to get her initial results so I can try to duplicate those results.
The second day I spent more time trying to download and install MATLAB and Carrie gave me a more detailed run-through of her project for Professor Xue's class and her results so far.
Wednesday Carrie was gone so I didn't come in.
Today I have spent the better part of the morning going through MATLAB tutorials and trying to get up to speed with how the program works. Carrie is going to give me some of the data she used to get her initial results so I can try to duplicate those results.
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