Updated methods for global locally interpolated estimation of alkalinity, pH, and nitrate

We have taken advantage of the release of version 2 of the Global Data Analysis Project data product (Olsen et al. 2016) to refine the locally interpolated alkalinity regression (LIAR) code for global estimation of total titration alkalinity of seawater (AT), and to extend the method to also produce estimates of nitrate (N) and in situ pH (total scale). The updated MATLAB software and methods are distributed as Supporting Information for this article and referred to as LIAR version 2 (LIARv2), locally interpolated nitrate regression (LINR), and locally interpolated pH regression (LIPHR). Collectively they are referred to as locally interpolated regressions (LIRs). Relative to LIARv1, LIARv2 has an 18% lower average AT estimate root mean squared error (RMSE), improved uncertainty estimates, and fewer regions in which the method has little or no available training data. LIARv2, LINR, and LIPHR produce estimates globally with skill that is comparable to or better than regional alternatives used in their respective regions. LIPHR pH estimates have an optional adjustment to account for ongoing ocean acidification. We have used the improved uncertainty estimates to develop LIR functionality that selects the lowest-uncertainty estimate from among possible estimates. Current and future versions of LIR software will be available on GitHub at https://github.com/BRCScienceProducts/LIRs.

Carter B. R., Feely R. A., Williams N. L., Dickson A. G. Fong M. B. & Takeshita Y., in press. Updated methods for global locally interpolated estimation of alkalinity, pH, and nitrate. Limnology and Oceanography: Methods. Article.

0 Responses to “Updated methods for global locally interpolated estimation of alkalinity, pH, and nitrate”



  1. Leave a Comment

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.




Subscribe to the RSS feed

Powered by FeedBurner

Follow AnneMarin on Twitter

Blog Stats

  • 1,123,766 hits

OA-ICC HIGHLIGHTS

Ocean acidification in the IPCC AR5 WG II

OUP book