Extreme events driving year-to-year differences in gross primary productivity across the US

Abstract. Solar-Induced chlorophyll Fluorescence (SIF) has previously been shown to strongly correlate with gross primary productivity (GPP), however this relationship has not yet been quantified for the recently launched TROPOspheric Monitoring Instrument (TROPOMI). Here we use a Gaussian mixture model to develop a parsimonious relationship between SIF from TROPOMI and GPP from flux towers across the conterminous United States (CONUS). The mixture model indicates the SIF-GPP relationship can be characterized by a linear model with two terms. We then estimate GPP across CONUS at 500-m spatial resolution over a 16-day moving window. We find that CONUS GPP varies by less than 4 % between 2018 and 2019. However, we observe four extreme precipitation events that induce regional GPP anomalies: drought in west Texas, flooding in the midwestern US, drought in South Dakota, and drought in California. Taken together, these events account for 28 % of the year-to-year GPP differences across CONUS.

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Ozone vegetation damage effects on gross primary productivity in the United States

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-13-31563-2013 ◽

2013 ◽

Vol 13 (12) ◽

pp. 31563-31605

Author(s):

X. Yue ◽

N. Unger

Keyword(s):

United States ◽

Primary Productivity ◽

The United States ◽

Gross Primary Productivity ◽

Scale Model ◽

Damage Effect ◽

The North ◽

The Us ◽

Line Process ◽

Vegetation Damage

Abstract. We apply an off-line process-based vegetation model to assess the impacts of ozone (O3) vegetation damage on gross primary productivity (GPP) in the United States (US) during the past decade (1998–2007). The model's GPP simulation is evaluated at 40 sites of the North American Carbon Program (NACP) synthesis. The ecosystem-scale model version reproduces interannual variability and seasonality of GPP at most sites, especially in croplands. Inclusion of the O3 damage impact decreases biases of simulated GPP at most of the NACP sites. The simulation with the O3 damage effect reproduces 64% of the observed variance in summer GPP and 45% on the annual average. Based on a regional gridded simulation over the US, summertime average O3-free GPP is 5.9 g C m−2 day−1 (9.1 g C m−2 day−1 in the East of 95° W and 3.7 g C m−2 day−1 in the West). O3 damage decreases GPP by 3–7% on average in the eastern US and leads to significant decreases of 13–17% in east coast hotspots. Sensitivity simulations show that a reduction of 25% in surface O3 concentration alleviates the average GPP damages to 1–3%, suggesting a promising prospect for ecosystem health following the emission control.

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Extreme events driving year-to-year differences in gross primary productivity across the US

Biogeosciences ◽

10.5194/bg-18-6579-2021 ◽

2021 ◽

Vol 18 (24) ◽

pp. 6579-6588

Author(s):

Alexander J. Turner ◽

Philipp Köhler ◽

Troy S. Magney ◽

Christian Frankenberg ◽

Inez Fung ◽

...

Keyword(s):

South Dakota ◽

Mixture Model ◽

Primary Productivity ◽

Extreme Precipitation ◽

Gaussian Mixture ◽

Gross Primary Productivity ◽

Moving Window ◽

Extreme Precipitation Events ◽

The Us ◽

Precipitation Events

Abstract. Solar-induced chlorophyll fluorescence (SIF) has previously been shown to strongly correlate with gross primary productivity (GPP); however this relationship has not yet been quantified for the recently launched TROPOspheric Monitoring Instrument (TROPOMI). Here we use a Gaussian mixture model to develop a parsimonious relationship between SIF from TROPOMI and GPP from flux towers across the conterminous United States (CONUS). The mixture model indicates the SIF–GPP relationship can be characterized by a linear model with two terms. We then estimate GPP across CONUS at 500 m spatial resolution over a 16 d moving window. We observe four extreme precipitation events that induce regional GPP anomalies: drought in western Texas, flooding in the midwestern US, drought in South Dakota, and drought in California. Taken together, these events account for 28 % of the year-to-year GPP differences across CONUS. Despite these large regional anomalies, we find that CONUS GPP varies by less than 4 % between 2018 and 2019.

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