Ms. Kathrin Linnemann Profile

Kathrin Linnemann

SPIE Involvement:

Author

Publications (1)

This will count as one of your downloads.

You will have access to both the presentation and article (if available).

DOWNLOAD NOW

This content is available for download via your institution's subscription. To access this item, please sign in to your personal account.

Email or Username Forgot your username?

Password Forgot your password?

Show

Keep me signed in

No SPIE account? Create an account

Proceedings Article | 16 October 2013 Paper

CDOM retrieval using measurements of downwelling irradiance

K. Linnemann, P. Gege, S. Rößler, T. Schneider, A. Melzer

Proceedings Volume 8888, 88880I (2013) https://doi.org/10.1117/12.2031250

KEYWORDS: Absorption, Sensors, Water, Atmospheric modeling, Statistical analysis, Optical properties, Data analysis, Statistical modeling, Carbon, Sun

Read Abstract +

As it can strongly influence the availability of light and thus primary production, coloured dissolved organic matter (CDOM) affects the function of lake ecosystems. Therefore reliable methods are required for the monitoring of CDOM concentration. A new method using downwelling irradiance was tested for applicability in four selected lakes of the Bavarian Osterseen Lake District, which consists of 19 naturally connected freshwater lakes of different trophic level. The method separates between the direct and diffuse part of the incident light in order to handle the strong variability of the underwater light field. It is implemented in the software WASI, which is capable to retrieve water constituents by inverse modeling. During field campaigns downwelling irradiance measurements using RAMSES sensors were made in different depths. Simultaneously, water samples were taken in three depths (0.5 m, 2 m and Secchi disk depth), from which the absorption coefficient of CDOM, a_Y, was derived in the range from 190 to 900 nm using photometric absorption measurements. Concentration (defined as a_Y at 440 nm) ranged from 0.33 to 1.55 m^-1 with a mean of 0.71 m^-1 ± 0.04 m^-1, the spectral slope at 440 nm from 0.0120 to 0.0184 nm-1 with a mean of 0.0145 ± 0.0008 nm^-1. These laboratory measurements from water samples were compared to CDOM concentration obtained by inverse modeling of downwelling irradiance measurements using WASI. For sensor depths lower than 1 to 1.5 m large uncertainties were observed. The measurements in 2 m depth and at Secchi disk depth yielded good correlation between water sample and WASI derived data (R² = 0.87) with a mean standard deviation of 0.06 m^-1 for the determined CDOM concentrations. This new method is an alternative to laboratory analysis of water samples from in situ measurements of CDOM concentration.

My Library

You currently do not have any folders to save your paper to! Create a new folder below.

Folder Name

Folder Description

View contact details

UPDATE YOUR PROFILE

Is this your profile? Update it now.

Sign into your SPIE.org account

Don’t have a profile and want one?

Create an account on SPIE.org

Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks. You are receiving this notice because your organization may not have SPIE eBooks access.*

*Shibboleth/Open Athens users─please sign in to access your institution's subscriptions.

To obtain this item, you may purchase the complete book in print or electronic format on SPIE.org.

ORGANIZATIONAL
Sign in with credentials provided by your organization.

Organizational Username

Organizational Password

Show/Hide Password

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available

Members:

Non-members: ADD TO CART

Keywords/Phrases

Search In:

Publication Years