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Level 3 Daily CO2, NO2

Posted: Wed Nov 22, 2023 11:43 am America/New_York
by jung_a

I am trying achieve a data from earthdata forum to use the information of CO2, NO2, CH4 values from the global map and investigate the relationship with the surface temperature in a global scale.
To achieve this, I've been exploring the L2 dataset (TES) from the earthdata forum, which provides variables for surface temperature and CO2, NO2, CH4 values.

However, the L2 dataset ncludes information gathered in the trail of the orbit and is not gridded.[0][v]=f&pg[0][gsk]=-start_date&fi=TES&fl=2%2B-%2BGeophys.%2BVariables%252C%2BSensor%2BCoordinates!3%2B-%2BGridded%2BObservations&tl=1700670674.569!3!!

For the sake of consistency and ease of analysis, I'm specifically looking for a daily L3 (gridded) dataset for CO2 and NO2 that also includes surface temperature information.

My questions are as follows:
- Is there a daily L3 (gridded) dataset available for CO2, NO2, and surface temperature?
- In the absence of an L3 dataset, is there a viable way to utilize the L2 dataset for my analysis?
- If neither option is feasible, do you have any recommendations for alternative daily datasets that could be suitable for my research interests?

I appreciate any insights, suggestions, or recommendations you may have regarding this matter.
Thank you.

Re: Level 3 Daily CO2, NO2

Posted: Mon Nov 27, 2023 12:16 pm America/New_York
by GES DISC - jimacker

The Giovanni system has daily Level 3 CO2, NO2, and CH4 from the Orbiting Carbon Observatory, the Ozone Measuring Instrument, and AIRS, respectively. I have created a URL for these variables in Giovanni, provided below. Note that for CH4 from AIRS, a pressure level must be provided. 1000 hPA is the best choice for Earth surface data.

Please reply for additional guidance on the use of the system; we will be glad to assist.

Re: Level 3 Daily CO2, NO2

Posted: Tue Nov 28, 2023 8:38 am America/New_York
by jung_a
Thank you for your prompt response!

I've observed that the CO2 dataset is generated using a sophisticated data assimilation technique, ensuring all values are populated. On the contrary, the NO2 and CH4 datasets seem to contain missing values, presumably arising from areas inaccessible for filling due to orbital constraints (gores between satellite paths)

Could you provide insights into potential methods for filling in these gaps in a manner similar to the approach used for the CO2 dataset?
Alternatively, do you recommend any datasets that have effectively addressed this issue?

Appreciate your assistance.

Re: Level 3 Daily CO2, NO2

Posted: Tue Nov 28, 2023 4:21 pm America/New_York
by GES DISC - jimacker
The daily data will usually have gaps due to satellite scanning patterns and conditions that affect data quality. I cannot provide a lot of insight on the OCO technique, except to note that because atmospheric CO2 is a well-mixed gas, it is computationally simpler to fill the gaps via assimilated data and other techniques. With quantities that are more variable spatially, these techniques may not be applicable. So my first recommendation is to examine the use of data products that are averaged over longer periods.