# Collaborative Research: NSF-SNSF: SCALE-UP - Understanding VPD impacts on forests across scales to advance the next generation of Earth-system models

> **NSF 01002627DB NSF RESEARCH & RELATED ACTIVIT** · Washington State University (WA) · $687,835

## Abstract

The dryness of the Earth's atmosphere (vapor pressure deficit, or VPD) is increasing. Its effects on many plant processes – from leaf photosynthesis, to tree growth and mortality, to forest production and water use – remain poorly understood. How does rising VPD affect different tree species growing in different locations? How do the effects of rising VPD on plants vary depending on the amount of moisture in the soil? How much and how quickly can plants cope with changes in VPD? And how do VPD effects operating on short-term, small-scale leaf processes translate to longer-term and larger-scale impacts on whole forests? Not knowing answers to these questions challenges researchers' ability to predict and manage forest responses to rapid changes in the environment. This project, termed SCALE-UP, is a partnership between institutions funded by the U.S. NSF and the NSF of Switzerland (SNSF) that enables a collaboration between U.S. and Swiss plant scientists and ecologists. This international team will examine the effects of rising VPD across vast distances and time scales using a cutting-edge combination of experiments, observations, and computer models. Not only will the project answer important scientific questions and advance fundamental knowledge about limited forest resources, it will also improve the ability of the U.S. and Switzerland to model, predict, and manage those resources. The scientists will utilize artificial intelligence (AI) approaches in their computer models, and will contribute to the U.S. AI national priority area by training the next generation of researchers in these techniques. By partnering internationally, U.S. researchers will gain access to unique resources, including a forest experiment in Switzerland that manipulates atmosphere and soil moisture, providing benefits to science and society in both countries.


SCALE-UP will leverage state-of-the-art controlled seedling experiments, the first in-vivo VPD and soil drought manipulation in 

## Key facts

- **NSF award ID:** 2530381
- **Awardee organization:** Washington State University (WA)
- **SAM.gov UEI:** XRJSGX384TD6
- **PI:** Nathan McDowell
- **Primary program:** 01002627DB NSF RESEARCH & RELATED ACTIVIT
- **All programs:** Artificial Intelligence (AI)
- **Estimated total:** $687,835
- **Funds obligated:** $687,835
- **Transaction type:** Standard Grant
- **Period:** 08/01/2026 → 07/31/2030

## Primary source

NSF Award Search: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2530381

## Citation

> US National Science Foundation, Award 2530381, Collaborative Research: NSF-SNSF: SCALE-UP - Understanding VPD impacts on forests across scales to advance the next generation of Earth-system models. Retrieved via AI Analytics 2026-06-26 from https://api.ai-analytics.org/grant/nsf/2530381. Licensed CC0.

---

*[NSF Awards dataset](/datasets/nsf-awards) · CC0 1.0*