Craig R. Ferguson

NASA · Science Mission Directorate

Changes in the spatiotemporal dynamics of the global water cycle will constitute some of the greatest challenges to socioeconomic-environmental well-being in a warming world. Large multimodel, multiscenario intercomparisons such as the Coupled Model Intercomparison Project Phase 5 (CMIP5) experiment support our best estimates of projected climate c...

In the context of forecasting societally impactful Great Plains low-level jets (GPLLJs), the potential added-value of satellite soil moisture (SM) data assimilation (DA) is high. GPLLJs are both sensitive to regional soil moisture gradients and frequent drivers of severe weather, including mesoscale convective systems. An untested hypothesis is tha...

A spectral analysis of Great Plains 850-hPa meridional winds (V850) from ECMWF’s coupled climate reanalysis of 1901-2010 (CERA-20C) reveals that their warm season (April-September) interannual variability peaks in May with 2-6 year periodicity, suggestive of an underlying teleconnection influence on low-level jets (LLJs). Using an objective, dynami...

The U.S. Great Plains warm season climate is inextricably linked to the frequency and structure of the region's southerly low‐level jet. In the present‐day climate (1977–2009), low‐level jets are shown to occur on 26%, 46%, and 62% of May–September days in the northern (NGP), central (CGP) and southern (SGP) Great Plains, respectively, and account...

We present a comparative analysis of atmospheric rivers (ARs) and Great Plains low-level jets (GPLLJs) in the central U.S. during April–September 1901–2010 using ECMWF’s CERA-20C. The analysis is motivated by a perceived need to highlight overlap and synergistic opportunities between traditionally disconnected AR and GPLLJ research. First, using th...

Accurate representation of the turbulent exchange of carbon, water, and heat between the land surface and the atmosphere is critical for modelling global energy, water, and carbon cycles, both in future climate projections and weather forecasts. We describe a Model Intercomparison Project (MIP) that compares the surface turbulent heat flux predicti...

Portions of the northeastern United States (NE) have experienced drought every year since 2016. The U.S. Drought Monitor (USDM) has played an important role in drought characterization and management by providing weekly drought maps across the entire United States, including the NE. Unfortunately, the USDM lacks consistency between input variables...

Knowledge of the seasonal positioning of the Intertropical Discontinuity (ITD) is critical to understanding seasonal moist convective processes and associated rainfall over West Africa. This study constitutes a new analysis of the seasonality of moist convection over West Africa, relative to the ITD, based on NASA's Atmospheric Infrared Sounder (AI...

Plain Language Summary Soil moisture (SM) widely varies in space and time. This variability critically influences freshwater availability, agriculture, ecosystem dynamics, climate and land‐atmosphere interactions, and it can also trigger hazards such as droughts, floods, landslides, and aggravate wildfires. Limited SM observational data constrained...

Soil moisture plays a key role in controlling land-atmosphere interactions, with implications for water resources, agriculture, climate, and ecosystem dynamics. Although soil moisture varies strongly across the landscape, current monitoring capabilities are limited to coarse-scale satellite retrievals and a few regional in-situ networks. Here, we i...

Sub-seasonal to seasonal (S2S) prediction, especially the prediction of extreme hydroclimate events such as droughts and floods, is not only scientifically challenging but has substantial societal impacts. Motivated by preliminary studies, the Global Energy and Water 20 Exchanges (GEWEX)/Global Atmospheric System Study (GASS) has launched a new ini...

Subseasonal-to-seasonal (S2S) prediction, especially the prediction of extreme hydroclimate events such as droughts and floods, is not only scientifically challenging, but also has substantial societal impacts. Motivated by preliminary studies, the Global Energy and Water Exchanges (GEWEX)/Global Atmospheric System Study (GASS) has launched a new i...

Sub-seasonal to seasonal (S2S) prediction, especially the prediction of extreme hydroclimate events such as droughts and floods, is not only scientifically challenging but has substantial societal impacts. Motivated by preliminary studies, the Global Energy and Water Exchanges (GEWEX)/Global Atmospheric System Study (GASS) has launched a new initia...

The Great Plains (GP) southerly nocturnal low-level jet (GPLLJ) is a dominant contributor to the region’s warm season (May–September) mean and extreme precipitation, wind energy generation and severe weather outbreaks—including mesoscale convective systems. The spatiotemporal structure, variability, and impact of individual GPLLJ events are closely...

The vertical profiles of temperature and water vapour from the Atmospheric InfraRed Sounder (AIRS) have been validated across various regions of the globe as an effort to provide a substitute for radiosonde observations. However, there is a paucity of inter-comparisons over West Africa where local convective processes dominate and radiosonde observ...

The Great Plains (GP) low-level jet (GPLLJ) contributes to GP warm season water resources (precipitation), wind resources, and severe weather outbreaks. Past research has shown that synoptic and local mesoscale physical mechanisms (Holton and Blackadar mechanisms) are required to explain GPLLJ variability. Although soil moisture-PBL interactions ar...

Low-level jets (LLJ) around the world critically support the food-, water-, and energy security in regions that they traverse. For the purposes of development planning and weather and climate prediction, it is important to improve understanding of how LLJs interact with the land surface and upper-atmospheric flow, and collectively, how LLJs have an...

Global “hot spots” for land–atmosphere coupling have been identified through various modeling studies—both local and global in scope. One hot spot that is common to many of these analyses is the U.S. southern Great Plains (SGP). In this study, we perform a mesoscale analysis, enabled by the Oklahoma Mesonet, that bridges the spatial and temporal ga...

A recent article published in the influential journal, Nature Communications, outlines a hypothetical evaporation engine that could harness the energy of lake water evaporation while simultaneously conserving the water resource. Its authors suggest that evaporation engines deployed across all US lakes and reservoirs could, collectively, yield up to...

Atmospheric rivers (ARs) are concentrated bands of water vapor that can cause extreme precipitation and severe flooding. Fortunately, due to their 1,500+ km spatial extent, they may also be forecasted days in advance. The goals of this study were to investigate the seasonal climatology of ARs in the Himalayan region of Nepal and to determine the ro...

Land–atmosphere (L-A) interactions are a main driver of Earth’s surface water and energy budgets; as such, they modulate near-surface climate, including clouds and precipitation, and can influence the persistence of extremes such as drought. Despite their importance, the representation of L-A interactions in weather and climate models remains poorl...

While investigating linkages between afternoon peak rainfall amount and land-atmosphere coupling strength, a statistically significant trend in phase 2 of the North American Land Data Assimilation System (NLDAS-2) warm season (April-September) afternoon (1700-2259 UTC) precipitation was noted for a large fraction of the conterminous United States,...

The multimodel Global Land-Atmosphere Coupling Experiment (GLACE) identified the semiarid Southern Great Plains (SGP) as a hotspot for land-atmosphere (LA) coupling and, consequently, landderived temperature and precipitation predictability. The area including and surrounding the U.S. Department of Energy Atmospheric Radiation Measurement (ARM) SGP...

As a basic form of climate patterns, the diurnal cycle of precipitation (DCP) can provide a key test bed for model reliability and development. In this study, the DCP over West Africa was simulated by the National Centers for Environmental Prediction (NCEP) Regional Spectral Model (RSM) during the monsoon season (April-September) of 2005. Three con...

potential use of continental fair-weather shallow cumuli as a way to retrieve the daily surface evaporative fraction over land is evaluated in convective conditions. The proposed method utilizes the fact that both the timing of cloud occurrence and the cloud-base height at the time of occurrence provide strong constraints on the surface energy bala...

Recent summers in the United States have been plagued by intense droughts that have caused significant damage to crops and have had a large impact on society. The ability to forecasts such events would allow for preparations that could help reduce the impact on society. Coupled land–atmosphere–ocean models were created to provide such forecasts but...

The Twentieth Century Reanalysis (20CR) holds the distinction of having the longest record length (140-year; 1871–2010) of any existing global atmospheric reanalysis. If the record can be shown to be homogenous, then it would be the first reanalysis suitable for long-term trend assessments, including those of the regional hydrologic cycle. On the o...

The ever-growing demand for applications in climate science, and particularly in the realm of climate change attribution has triggered a paradigm shift in reanalysis production towards so-called "climate-quality" reanalyses. Climate-quality reanalyses seek to ameliorate the issue of unphysical time-varying biases through the assimilation of only th...

Droughts represent a significant source of social and economic damage in the southeast United States. Having sufficient warning of these extreme events enables managers to prepare for and potentially mitigate the severity of their impacts. A seasonal hydrologic forecast system can provide such warning, but current forecast skill is low during the c...

Land-atmosphere coupling strength or the degree to which land surface anomalies influence boundary layer development and in extreme cases, rainfall is arguably the single most fundamental criterion for evaluating hydrological model performance. The Global Land Atmosphere Coupling Experiment (GLACE) showed that strength of coupling and its represent...

The Twentieth Century Reanalysis (20CR), which spans the 138 year period from 1871 to 2008, was intended for a variety of climate applications, including long-term trend assessment. Because over land 20CR only assimilates surface pressure observations and their count increases by an order of magnitude over the course of the record, a key question i...

The lack of observational data for use in evaluating the realism of model-based land-atmosphere feedback signal and strength has been deemed a major obstacle to future improvements to seasonal weather prediction by the Global Land-Atmosphere Coupling Experiment (GLACE). To address this need, a 7-yr (2002-09) satellite remote sensing data record is...

Three process based models are used to estimate terrestrial heat fluxes and evapotranspiration (ET) at the global scale: a single source energy budget model, a Penman–Monteith based approach, and a Priestley–Taylor based approach. All models adjust the surface resistances or provide ecophysiological constraints to account for changing environmental...

Evaporation from water or soil surfaces and transpiration from plants combine to return available water at the surface layer back to the bulk atmosphere in a process called evapotranspiration. Much of our understanding of the complex feedback mechanisms between the Earth’s surface and the surrounding atmosphere is focused on quantifying this proce...

The skill of instantaneous Atmospheric Infrared Sounder (AIRS) retrieved near-surface meteorology, including surface skin temperature (Ts), air temperature (Ta), specific humidity (q), and relative humidity (RH), as well as model-derived surface pressure (Psurf) and 10-m wind speed (w), is evaluated using collocated National Climatic Data Center (N...

Nine satellite-based products, each of which provides information about land surface water budget terms, are used to estimate seasonal and annual variations in the water budget of the major river basins of the conterminous USA from 2003 to 2006. The remotely sensed terms are compared with gridded gauge precipitation, and estimates of evapotranspira...

We calculate evapotranspiration (E) from remote sensing (RS) data using the Penman–Monteith model over continental USA for four years (2003–2006) and explore, through an ensemble generation framework, the impact of input dataset (meteorological, radiation and vegetation) selection on performance (uncertainty) at the monthly time-scale. The impact o...

This dissertation is devoted to the improved observation, understanding, and modeling of the global hydrological cycle through the integration of data from satellite remote sensing. Recent advancements in retrieval algorithms and the maturation of numerous satellite missions have made available an unprecedented record of land surface and atmospheri...

Deriving overland evapotranspiration (ET) estimates is an important part of the larger effort to develop long-term Earth System Data Records (ESDRs) for the major components (storages and fluxes) of the terrestrial water cycle. Recent progress towards this has involved the development of ET datasets using both observational and modeling approaches...

The increasing availability of remote sensing products for all components of the terrestrial water cycle makes it now possible to evaluate the potential of water balance closure purely from remote sensing sources. We take precipitation (P) from the TMPA and CMORPH products, a Penman-Monteith based evapotranspiration (E) estimate derived from NASA A...

Air temperature and vapor pressure deficit (VPD) are closely related to sensible and latent heat fluxes and the surface energy budget on synoptic and seasonal timescales. Uncertainty regarding the surface meteorology inputs for regional land surface models constrains model based estimation of land-atmosphere energy and water fluxes. A sparse surfac...

Modern remote sensing (RS) platforms now offer measurements of the Earth's surface (and atmosphere) at unprecedented spatial and temporal coverage, with minimal latency. The use of these data in regional to global hydrologic studies has shown particular promise, particularly for evapotranspiration (ET), a key, but under-observed hydrologic variable...

The magnitude of the key terms in the terrestrial water balance at global and continental scales is surprisingly poorly known. Neither in situ observations nor land surface modeling is of sufficient accuracy to close the water balance through independent estimates of the terms. Remote sensing provides a basis for near-independent estimation of some...

Understanding the coupling strength between land and its overlying boundary layer is important to establishing the role of the surface state in boundary layer development and related processes. Much of our current understanding has resulted from model diagnostics carried out by Alan K. Betts using the European Center's (ECMWF) forecast and reanalys...

Documenting the global water and energy cycle through modeling and observations is fundamental to achieving the goals of the World Climate Research Programme's Global Energy and Water Cycle Experiment (GEWEX), and similar national programs like NASA's Energy and Water Cycle Study (NEWS) that support GEWEX research. This documentation is needed to a...

The measurement of climatic variables from space is essential for understanding the role of terrestrial hydrosphere-biosphere in the Earth's climate system. Amongst the climatic variables surface latent heating (or Evapotranspiration - ET) is often considered as the climate linchpin variable since it plays a vital link between the global hydrologic...

An operational global soil moisture data product is currently generated from the observations of the Advanced Microwave Scanning Radiometer (AMSR-E) aboard NASA's Aqua satellite using the retrieval procedure described in Njoku and Chan [Njoku, E.G. and Chan, S.K., 2006. Vegetation and surface roughness effects on AMSR-E land observations, remote se...

A multi-sensor Earth Observing System evapotranspiration (ET) algorithm and product, referred to as MOD16, will be presented here. The original MOD16 algorithms were based on remote sensing data solely from the Moderate Resolution Imaging Spectroradiometer (MODIS) and evolved first from an empirical relationship between MODIS vegetation surface tem...

Traditional efforts to quantify the value of remotely-sensed soil moisture retrievals via comparison to ground- based measurements have been hindered by inconsistencies in spatial and temporal scales between the two products. A new method was developed to assess the "skill" of remotely-sensed soil moisture retrievals that does not require ground ob...