Browsed by
Tag: methane

How to Correct an Erroneous Calibration for the LI-7700 Open Path Methane Analyzer

How to Correct an Erroneous Calibration for the LI-7700 Open Path Methane Analyzer

The LI-77000 analyzer provides the facility for users to calibrate using standard calibration gases. This option can be used to assure users that the instrument is performing according to specification. However, a mistake or an error in the calibration of the LI-7700 will result in incorrect zero (kz) and span (ks) multipliers. As a result, the computed methane density according to equation 6-12 of the LI-7700 Instruction Manual will be incorrect.

equation1a Read More Read More

Recent Publications using the LI-7700 Open Path Methane Analyzer

Recent Publications using the LI-7700 Open Path Methane Analyzer

The LI-7700 Open Path Ch4 Analyzer is a lightweight, low power, low maintenance analyzer  ideal for making high performance measurements in extreme environments. But don’t take our word for it – see how other researchers are using this analyzer to achieve high quality results:

  • Alberto, Ma C. R, Reiner Wassmann, Roland J. Buresh, James R. Quilty, Teodoro Q. Correa, Joseph M. Sandro, and Caesar A. R. Centeno. “Measuring Methane Flux from Irrigated Rice Fields by Eddy Covariance Method Using…

    Read More Read More

Diagnostic Settings for the LI-7500/7500A/7200/7700 in EddyPro Software

Diagnostic Settings for the LI-7500/7500A/7200/7700 in EddyPro Software

Diagnostics are used to indicate whether your instrument is operating correctly. The LI-7500 and LI-7500A Open Path CO2/H2O Analyzers output integers between 0 and 255 that correspond to as many as 5 diagnostic values. The diagnostic values of the LI-7200 Enclosed CO2/H2O Analyzer and LI-7700 Open Path CH4 Analyzer are integers between 0 and 65535 that indicate up to 10 and 16 diagnostics, respectively. A detailed explanation of the diagnostic values for the LI-7500A and LI-7200 and how to decipher…

Read More Read More

Filtering LI-7700 high frequency data using diagnostic value information

Filtering LI-7700 high frequency data using diagnostic value information

The LI-7700 outputs a variable titled DIAG – Diagnostic Value, at the same output rate as the measured data stream which can be used to filter the raw high frequency data. The diagnostic value from the LI-7700 is a 16-bit number that can be broken down to the 16 individual bits to identify various diagnostic information about the instrument.  When processing LI-7700 data for Eddy covariance measurements, the raw data needs to be filtered to exclude situations when the measured…

Read More Read More

LI-COR Presents Landfill Methane Emission Data at Global Waste Management Symposium

LI-COR Presents Landfill Methane Emission Data at Global Waste Management Symposium

Measuring greenhouse gas emissions at landfills using continuous monitoring offers new insight in estimating total annual emissions. LI-COR Principal Scientist, Liukang Xu presented methane emission data collected from a landfill at Global Waste Management Symposium in Phoenix, AZ on October 1st, 2012 and discussed the advantages of continuous monitoring over traditional interval monitoring. In the United States, the Environmental Protection Agency (USEPA) has recently enacted a new rule related to the mandatory reporting of greenhouse gases, which requires some municipal…

Read More Read More