E. Natasha Stavros

California Institute of Technology | CIT · Jet Propulsion Laboratory

Observations of planet Earth from space are a critical resource for science and society. Satellite measurements represent very large investments and United States (US) agencies organize their effort to maximize the return on that investment. The US National Research Council conducts a survey of Earth science and applications to prioritize observati...

Spectroscopic reflectance data provide novel information on the properties of the Earth's terrestrial and aquatic surfaces. Until recently, imaging spectroscopy missions were dependent mainly on airborne instruments, such as the Next Generation Airborne Visible InfraRed Imaging Spectrometer (AVIRIS‐NG), providing limited spatial and temporal observ...

Fire is an integral component of ecosystems globally and a tool that humans have harnessed for millennia. Altered fire regimes are a fundamental cause and consequence of global change, impacting people and the biophysical systems on which they depend. As part of the newly emerging Anthropocene, marked by human-caused climate change and radical chan...

Topography, climate and plant water stress influence the spatial patterns of burn severity (damage to soils and vegetation associated with wildfires); however, the relative importance of these predictors remains contested. We hypothesized that high‐resolution pre‐fire vegetation water stress, measured using evapotranspiration (ET), evaporative stre...

The decline in biodiversity in Mediterranean-type ecosystems (MTEs) and other shrublands underscores the importance of understanding the trends in species loss through consistent vegetation mapping over broad spatial and temporal ranges, which is increasingly accomplished with optical remote sensing (imaging spectroscopy). Airborne missions planned...

Increasing fire impacts across North America are associated with climate and vegetation change, greater exposure through development expansion, and less-well studied but salient social vulnerabilities. We are at a critical moment in the contemporary human-fire relationship, with an urgent need to transition from emergency response to proactive meas...

The Surface Biology and Geology (SBG) concept is the first National Aeronautics and Space Administration (NASA) Earth mission to develop and implement systematic integration of science application needs at the architecture study stage. Prior NASA mission concept and planning activities presumed that science measurement needs would encompasss applic...

Overview: Wicked problems result from complex systems and often have no single solution. WKID Innovation, a framework to tackle wicked problems, is modeled after the National Aeronautic Space Administration’s (NASA) science system engineering. NASA is a leader creating disruptive technologies that alter the way that people, companies, and industrie...

A fundamental challenge in verifying urban CO2 emissions reductions is estimating the biological influence that can confound emission source attribution across heterogeneous and diverse landscapes. Recent work using atmospheric radiocarbon revealed a substantial seasonal influence of the managed urban biosphere on regional carbon budgets in the Los...

NOW PUBLISHED IN _RESEARCH-TECHNOLOGY MANAGEMENT_, HTTPS://DOI.ORG/10.1080/08956308.2022.1994249 [https://doi.org/10.1080/08956308.2022.1994249] Wicked problems result from complex systems and often have no single solution. WKID Innovation is a framework to tack wicked problems and is modeled after NASA’s science system engineering. NASA is a leade...

National Academies' Decadal Survey, Thriving on Our Changing Planet, recommended Surface Biology and Geology (SBG) as a "Designated Targeted Observable" (DO). The SBG DO is based on the need for capabilities to acquire global, high spatial resolution, visible to shortwave infrared (VSWIR; 380-2500 nm; ~30 m pixel resolution) hyperspectral (imaging...

It is important to understand the distribution of irrigated and non-irrigated vegetation in rapidly expanding urban areas that are experiencing climate-induced changes in water availability, such as Los Angeles, California. Mapping irrigated vegetation in Los Angeles is necessary for developing sustainable water use practices and accurately account...

Providing accurate information on fire effects is critical to understanding post-fire ecological processes and to design appropriate land management strategies. Multispectral imagery from optical passive sensors is commonly used to estimate fire damage, yet this type of data is only sensitive to the effects in the upper canopy. This paper evaluates...

The NASA open data policy and the increases in data volume from recent and future missions have resulted in a need to re-evaluate data archive information systems and services. For example, the Surface Water Ocean Topography mission (SWOT) will produce ∼15 TB of data every day that needs to be freely and openly accessible through the NASA Physical...

High spatial resolution maps of Los Angeles, California are needed to capture the heterogeneity of urban land cover while spanning the regional domain used in carbon and water cycle models. We present a simplified framework for developing a high spatial resolution map of urban vegetation cover in the Southern California Air Basin (SoCAB) with publi...

Traditional methods for assessing fire danger often depend on meteorological forecasts, which have reduced reliability after ∼10 d. Recent studies have demonstrated long lead-time correlations between pre-fire-season hydrological variables such as soil moisture and later fire occurrence or area burned, yet the potential value of these relationships...

Wildfire danger assessment is essential for operational allocation of fire management resources; with longer lead prediction, the more efficiently can resources be allocated regionally. Traditional studies focus on meteorological forecasts and fire danger index models (e.g., National Fire Danger Rating System-NFDRS) for predicting fire danger. Mete...

Wildfire has had increasing impacts on society as the climate changes and the wildland urban interface grows. As such, there is a demand for innovative solutions to help manage fire. Managing wildfire can include proactive fire management such as prescribed burning within constrained areas or advancements for reactive fire management (e.g., fire su...

Global ecology – the study of the interactions among the Earth's ecosystems, land, atmosphere, and oceans – depends crucially on global observations: this paper focuses on space‐based observations of global terrestrial ecosystems. Early global ecology relied on extrapolation of detailed site‐level observations, using models of increasing complexity...

Traditional methods for assessing fire danger often depend on meteorological forecasts, which have reduced reliability after ~ 10 days. Recent studies have demonstrated long lead-time correlations between pre-fire-season hydrological variables such as soil moisture and later fire occurrence or area burned, yet no potential value of these relationsh...

Hypotheses that megafires ‐ very large, high impact fires ‐ are caused by either climate effects such as drought or fuel accumulation due to fire exclusion with accompanying changes to forest structure have long been alleged and guided policy but their physical basis remains untested. Here, unique airborne observations and microscale simulations us...

To protect ecosystem services and the increasing wildland urban interface in a world with fire, comprehensive maps of wildland fuels are needed to predict fire behavior and effects. Traditionally, fuels have been categorized into a classification scheme whereby a single metric represents vegetation composition and structure, which can then be param...

In 2018 technologies on the International Space Station will provide ~1 year of synchronous observations of ecosystem composition, structure and function. We discuss these instruments and how they can be used to constrain global models and improve our understanding of the current state of terrestrial ecosystems.

Over the past decade, there has been an increase in the use of NASA's Earth Observing System (EOS) data and imagery for time-sensitive applications such as monitoring wildfires, floods, and extreme weather events. In September 2016, NASA sponsored a workshop for data users, producers, and scientists to discuss the needs of time-sensitive science ap...

In 2018 technologies on the International Space Station will provide ~1 year of synchronous observations of ecosystem composition, structure and function. We discuss these instruments and how they can be used to constrain global models and improve our understanding of the current state of terrestrial ecosystems.

https://www.nature.com/articles/s41559-017-0194

Megafires have lasting social, ecological, and economic impacts and are increasing in the western contiguous United States. Because of their infrequent nature, there is a limited sample of megafires to investigate their unique behaviour, drivers and relationship to forest management practices. One approach is to characterize critical information pr...

Saturn's moon Enceladus offers a unique opportunity in the search for life and habitable environments beyond Earth, a key theme of the National Research Council's 2013-2022 Decadal Survey. A plume of water vapor and ice spews from Enceladus's south polar region. Cassini data suggest that this plume, sourced by a liquid reservoir beneath the moon's...

Future climate change and its effects on social and ecological systems present challenges for preserving valued ecosystem services, including local and regional air quality. Wildfire is a major source of air-quality impact in some locations, and a substantial contributor to pollutants of concern, including nitrogen oxides and particulate matter, wh...

Seasonal changes in the climatic potential for very large wildfires (VLWF≥ 50,000 ac~20,234 ha) across the western contiguous United States are projected over the 21st century using generalized linear models and downscaled climate projections for two representative concentration pathways (RCPs). Significant (p≤0.05) increases in VLWF probability fo...

Very large wildfires can cause significant economic and environmental damage, including destruction of homes, adverse air quality, firefighting costs and even loss of life. We examine how climate is associated with very large wildland fires (VLWFs $50 000 acres, or ,20 234 ha) in the western contiguous USA. We used composite records of climate and...

Background/Question/Methods In August 2013, a major fire in Yosemite National Park and the Stanislaus National Forest burned 104,131 hectares (257,314 acres) before extinction on October 24th, 2013 (http://inciweb.nwcg.gov/incident/3660/). One of the unique attributes of this fire is the unprecedented amount of before and after remotely sensed da...

This year two of NASA's Earth missions, Orbiting Carbon Observatory 2 (OCO-2; http://oco.jpl.nasa.gov) and Soil Moisture Active Passive (SMAP; http://smap.jpl.nasa.gov), will collect data relating to water and carbon cycles at unprecedented spatial and temporal resolutions. Synthesizing these data provides unique opportunities for understanding int...

Smoke from wildfires has adverse biological and social consequences, and various lines of evidence suggest that smoke from wildfires in the future may be more intense and widespread, demanding that methods be developed to address its effects on people, ecosystems, and the atmosphere. In this paper, we present the essential ingredients of a modeling...

Smoke from wildfires has adverse biological and social consequences, and various lines of evidence suggest that smoke from wildfires in the future may be more intense and widespread, demanding that methods be developed to address its effects on people, ecosystems, and the atmosphere. In this paper, we present the essential ingredients of a modeling...

Global change will clearly have a significant impact on the environment. Among the concerns for future air quality in the United States, intercontinental transport of pollution has become increasingly important. In this study, we examined the effect of the changes in chemical boundary conditions, including the upper troposphere, and emissions from...

Wildfires can have an important impact on regional air quality as they are large and intermittent sources of primary particulates, secondary aerosols, and ozone precursors. As part of an ongoing analysis on the effects of global change upon US air quality, we report results for current and future decade simulations of the inter-relationship among c...

Expected changes in climate are thought to increase the chance of large intense fires. Anticipating extreme fire events is an important component of broad-scale land management and allocation of firefighting resources. We are developing two models for large fire occurrence and size as a function of environmental conditions, with the goal of predict...

It is widely accepted in both scientific and political communities such as the Intergovernmental Panel on Climate Change (IPCC) and the Environmental Protection Agency (EPA), that climate is changing. Previous studies have shown that expected changes in climate will increase the severity of wild fire. It is necessary to assess the impact of global...

There is limited information about the relative magnitude of the spectral variations in the ionizing component of solar irradiance on solar cycle time scales. We found that the TIMED/SEE Version 9 irradiance values predict relatively more ionospheric heating at solar minimum than those from Version 8. These changes have direct impacts on solar cycl...

There is limited information about the relative magnitude of the spectral variations in the ionizing component of solar irradiance on solar cycle timescales. We found that the Thermosphere, Ionosphere, Mesosphere, Energetics, and Dynamics (TIMED)/Solar Extreme Ultraviolet Experiment (SEE) Version 9 irradiance values predict relatively more ionosphe...

We report observations of 10 eV to 1 keV photoelectrons produced by 1-50 nm solar irradiance during the Whole Heliosphere Interval (WHI). The observations were made from the FAST satellite at ~ 3,000 km. From March 20 to April 16, 2008 we found minimal (ie ~10%) variation in photoelectron flux at 25 eV, generated by EUV irradiance in the 27-31 nm r...