About Us

Climate information is abundant. Knowing how to use it well is hard.

Degree Day helps organizations understand, evaluate, and apply climate-related information for infrastructure and asset decisions.

Meet the team

Past roles at:

NOAA, Arup, Ramboll, and WSP

15+

years of expertise

in physical climate science and impacts, engineering, and natural disaster policy

Who We Are

Climate models, hazard maps, risk scores, and climate reports are more accessible than ever. Understanding when they should and should not be used remains difficult.

Datasets often disagree. Models have limitations. Hazard scores can hide critical assumptions. Many tools provide answers without explaining when they should, and should not, be trusted.

Degree Day was founded to help organizations navigate this complexity.

We help clients understand, evaluate, and apply climate-related information for infrastructure, asset, and capital decisions. Our work focuses on what climate information can and cannot tell you, so decisions are grounded in evidence, uncertainty, and the realities of the problem being solved.

We are an independent weather and climate analytics firm serving businesses, engineering firms, utilities, asset managers, and public agencies that need technically rigorous analysis rather than generic climate data.

Our Mission

Degree Day helps people understand, evaluate, and apply climate-related information for real-world decisions.

We believe climate information should be transparent, understandable, and decision-relevant. Our goal is not to provide certainty where it does not exist, but to help organizations make informed decisions using the best available evidence.

Our Approach

We start with the decision, not the dataset.

Climate models, observations, hazard maps, and risk scores can all be useful. They can also be misapplied. Understanding their strengths, limitations, and appropriate use is often more important than selecting a particular model or dataset.

Our work combines observations, climate science, engineering judgment, and transparent uncertainty analysis. Sometimes that means identifying a material climate risk. Sometimes it means explaining why a dataset, model, or conclusion is not fit for purpose.

We do not start with a narrative and work backward. We begin with the decision being made, the evidence available, and the limits of what can reasonably be known.

The result is analysis that is transparent, technically defensible, and designed to hold up under engineering, regulatory, and stakeholder review.

Our Research

Peer-reviewed science behind every recommendation

Explore all research

2026 · Environmental Research: Climate

Multivariate Bias Correction of ERA5 Using in-situ Observations for Planning and Engineering

2025 · Nature Climate Change

Observations reveal changing coastal storm extremes around the United States

2017 · Science

Estimating economic damage from climate change in the United States

Our Values

Evidence before narrative

We start with the evidence, not a predetermined conclusion. Our role is to understand what the data supports, what remains uncertain, and what can reasonably be inferred from the available information.

Understand limitations

Climate models, observations, hazard maps, and risk scores all have strengths and limitations. We believe better decisions come from understanding those limitations, not ignoring them.

Decision-focused

Climate information is only useful when it informs a real decision. We focus on the questions being asked, the consequences of being wrong, and the information needed to support practical action.

Leadership & Advisors

Our Team

D.J. Rasmussen, PhD

Founder and Principal

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D.J. Rasmussen is the Founder and Principal of Degree Day. He has provided expert guidance and conducted cutting-edge research on the technical, strategic, and policy challenges posed by climate risks for over 15 years.

D.J. has collaborated with Fortune 500 companies, data center operators, federal and state government agencies, utilities, and transit organizations to develop tailored strategies for managing extreme weather and climate-related risks and enhancing resilience.

Previously, he held roles at multinational engineering firms and was a research fellow at Princeton University and NOAA's Geophysical Fluid Dynamics Laboratory, a pioneering institution in atmosphere-ocean climate modeling.

His expertise is reflected in numerous technical reports and peer-reviewed research published in leading scientific journals, including Science and Nature Climate Change. He received his PhD in Applied Climate Science, Impacts, and Policy from Princeton University.

Dave Rasmussen, MBA

Strategic Advisor

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Dave Rasmussen provides strategic business guidance to Degree Day, drawing on over four decades of experience building and leading successful engineering consulting companies. He founded Turbine Consultants, Inc. in 1984, growing it into a recognized leader in steam and gas turbine failure analysis and repair services. Under his leadership, the company appeared multiple times on the Inc. 500 list of America's fastest-growing private companies before being acquired by Mechanical Dynamics & Analysis (MD&A) in 2001, and subsequently by Hitachi Power Systems in 2005.

Mr. Rasmussen holds a B.S. in Mechanical Engineering from the University of Wisconsin-Milwaukee and an MBA from Kent State University. His expertise in engineering services, contract management, and scaling technical consulting businesses provides valuable perspective as Degree Day expands its climate risk analytics and advisory services.

James Poplawski

Technical Advisor — IT Infrastructure

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James Poplawski serves as Technical Advisor for IT Infrastructure at Degree Day, providing expertise in network architecture, cloud connectivity, and data systems. With over 20 years of experience in network engineering and infrastructure, Mr. Poplawski has designed and implemented high-performance hybrid-WAN and cloud architectures for major financial services firms and enterprise organizations, including Moody's Corporation, Invesco, OppenheimerFunds, and Fanatics.

Mr. Poplawski holds a Bachelor's degree in Information Technology from Colorado State University Global and an Associate's degree in Computer Information Systems from Nicolet College. He maintains multiple industry certifications including CCNA, CCNP, Network+, and CompTIA Project+. His guidance supports Degree Day's data infrastructure, security, and systems architecture.

Where We Are

Coast to coast

San Diego

1001 Garnet Ave, San Diego, CA 92109

Pacific Time (UTC −8 / −7)

Denver

Colorado, USA

Mountain Time (UTC −7 / −6)

Naples

Florida, USA

Eastern Time (UTC −5 / −4)

Speak With Us

Email Us Book an intro call