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DAF RELEASES UPDATE ON TELEWORK AND REMOTE WORK GUIDANCE
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By NASA
8 min read
Preparations for Next Moonwalk Simulations Underway (and Underwater)
Return to 2024 SARP Closeout Faculty Advisors:
Dr. Tom Bell, Woods Hole Oceanographic Institution
Dr. Kelsey Bisson, NASA Headquarters Science Mission Directorate
Graduate Mentor:
Kelby Kramer, Massachusetts Institute of Technology
Kelby Kramer, Graduate Mentor
Kelby Kramer, graduate mentor for the 2024 SARP Ocean Remote Sensing group, provides an introduction for each of the group members and shares behind-the scenes moments from the internship.
Lucas DiSilvestro
Shallow Water Benthic Cover Type Classification using Hyperspectral Imagery in Kaneohe Bay, Oahu, Hawaii
Lucas DiSilvestro
Quantifying the changing structure and extent of benthic coral communities is essential for informing restoration efforts and identifying stressed regions of coral. Accurate classification of shallow-water benthic coral communities requires high spectral and spatial resolution, currently not available on spaceborne sensors, to observe the seafloor through an optically complex seawater column. Here we create a shallow water benthic cover type map of Kaneohe Bay, Oahu, Hawaii using the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) without requiring in-situ data as inputs. We first run the AVIRIS data through a semi-analytical inversion model to derive color dissolved organic matter, chlorophyll concentration, bottom albedo, suspended sediment, and depth parameters for each pixel, which are then matched to a Hydrolight simulated water column. Pure reflectance for coral, algae, and sand are then projected through each water column to create spectral endmembers for each pixel. Multiple Endmember Spectral Mixture Analysis (MESMA) provides fractional cover of each benthic class on a per-pixel basis. We demonstrate the efficacy of using simulated water columns to create surface reflectance spectral endmembers as Hydrolight-derived in-situ endmember spectra strongly match AVIRIS surface reflectance for corresponding locations (average R = 0.96). This study highlights the capabilities of using medium-fine resolution hyperspectral imagery to identify fractional cover type of localized coral communities and lays the groundwork for future spaceborne hyperspectral monitoring of global coral communities.
Atticus Cummings
Quantifying Uncertainty In Kelp Canopy Remote Sensing Using the Harmonized Landsat Sentinel-2 Dataset
Atticus Cummings
California’s giant kelp forests serve as a major foundation for the region’s rich marine biodiversity and provide recreational and economic value to the State of California. With the rising frequency of marine heatwaves and extreme weather onset by climate change, it has become increasingly important to study these vital ecosystems. Kelp forests are highly dynamic, changing across several timescales; seasonally due to nutrient concentrations, waves, and predator populations, weekly with typical growth and decay, and hourly with the tides and currents. Previous remote sensing of kelp canopies has relied on Landsat imagery taken with a eight-day interval, limiting the ability to quantify more rapid changes. This project aims to address uncertainty in kelp canopy detection using the Harmonized Landsat and Sentinel-2 (HLS) dataset’s zero to five-day revisit period. A random forest classifier was used to identify pixels that contain kelp, on which Multiple Endmember Spectral Mixture Analysis (MESMA) was then run to quantify intrapixel kelp density. Processed multispectral satellite images taken within 3 days of one another were paired for comparison. The relationship between fluctuations in kelp canopy density with tides and currents was assessed using in situ data from an acoustic doppler current profiler (ADCP) at the Santa Barbara Long Term Ecological Research site (LTER) and a NOAA tidal buoy. Preliminary results show that current and tidal trends cannot be accurately correlated with canopy detection due to other sources of error. We found that under cloud-free conditions, canopy detection between paired images varied on average by 42%. Standardized image processing suggests that this uncertainty is not created within the image processing step, but likely arises due to exterior factors such as sensor signal noise, atmospheric conditions, and sea state. Ultimately, these errors could lead to misinterpretation of remotely sensed kelp ecosystems, highlighting the need for further research to identify and account for uncertainties in remote sensing of kelp canopies.
Jasmine Sirvent
Kelp Us!: A Methods Analysis for Predicting Kelp Pigment Concentrations from Hyperspectral Reflectance
Jasmine Sirvent
Ocean color remote sensing enables researchers to assess the quantity and physiology of life in the ocean, which is imperative to understanding ecosystem health and formulating accurate predictions. However, without proper methods to analyze hyperspectral data, correlations between spectral reflectance and physiological traits cannot be accurately derived. In this study, I explored different methods—single variable regression, partial least squares regressions (PLSR), and derivatives—in analyzing in situ Macrocystis pyrifera (giant kelp) off the coast of Santa Barbara, California in order to predict pigment concentrations from AVIRIS hyperspectral reflectance. With derivatives as a spectral diagnostic tool, there is evidence suggesting high versus low pigment concentrations could be diagnosed; however, the fluctuations were within 10 nm of resolution, thus AVIRIS would be unable to reliably detect them. Exploring a different method, I plotted in situ pigment measurements — chlorophyll a, fucoxanthin, and the ratio of fucoxanthin to chlorophyll a—against hyperspectral reflectance that was resampled to AVIRIS bands. PLSR proved to be a more successful model because of its hyperdimensional analysis capabilities in accounting for multiple wavelength bands, reaching R2 values of 0.67. Using this information, I constructed a model that predicts kelp pigments from simulated AVIRIS reflectance using a spatial time series of laboratory spectral measurements and photosynthetic pigment concentrations. These results have implications, not only for kelp, but many other photosynthetic organisms detectable by hyperspectral airborne or satellite sensors. With these findings, airborne optical data could possibly predict a plethora of other biogeochemical traits. Potentially, this research would permit scientists to acquire data analogous to in situ measurements about floating matters that cannot financially and pragmatically be accessed by anything other than a remote sensor.
Isabelle Cobb
Correlations Between SSHa and Chl-a Concentrations in the Northern South China Sea
Isabelle Cobb
Sea surface height anomalies (SSHa)–variations in sea surface height from climatological averages–occur on seasonal timescales due to coastal upwelling and El Niño-Southern Oscillation (ENSO) cycles. These anomalies are heightened when upwelling plumes bring cold, nutrient-rich water to the surface, and are particularly strong along continental shelves in the Northern South China Sea (NSCS). This linkage between SSHa and nutrient availability has interesting implications for changing chlorophyll-a (chl-a) concentrations, a prominent indicator of phytoplankton biomass that is essential to the health of marine ecosystems. Here, we evaluate the long-term (15 years) relationship between SSHa and chl-a, in both satellite remote sensing data and in situ measurements. Level 3 SSHa data from Jason 1/2/3 satellites and chl-a data from MODIS Aqua were acquired and binned to monthly resolution. We found a significant inverse correlation between SSHa and chl-a during upwelling months in both the remote sensing (Spearman’s R=-0.57) and in situ data, with higher resolution in situ data from ORAS4 (an assimilation of buoy observations from 2003-2017) showing stronger correlations (Spearman’s R=-0.75). In addition, the data reveal that the magnitude of SSH increases with time during instances of high correlation, possibly indicating a trend of increased SSH associated with reduced seasonal chl-a concentrations. Thus, this relationship may inform future work predicting nutrient availability and threats to marine ecosystems as climate change continues to affect coastal sea surface heights.
Alyssa Tou
Exploring Coastal Sea Surface Temperature Anomalies and their effect on Coastal Fog through analyzing Plant Phenology
Alyssa Tou
Marine heat waves (MHW) have been increasing in frequency, duration and intensity, giving them substantial potential to influence ecosystems. Do these MHWs sufficiently enhance coastal precipitation such that plant growth is impacted? Recently, the Northeast Pacific experienced a long, intense MHW in 2014/2015, and another short, less intense MHW in 2019/2020. Here we investigate how the intensity and duration of MHWs influence the intensity and seasonal cycle of three different land cover types (‘grass’, ‘trees’, and a combination of both ‘combined’’) to analyze plant phenology trends in Big Sur, California. We hypothesize that longer intense MHWs decrease the ocean’s evaporative capacity, decreasing fog, thus lowering plant productivity, as measured by Normalized Difference Vegetation Index (NDVI). Sea surface temperature (SST) and NDVI data were collected from the NOAA Coral Reef Watch, and NASA MODIS/Terra Vegetation Indices 16-Day L3 Global 250m products respectively. Preliminary results show no correlation (R2=0.02) between SSTa and combined NDVI values and no correlation (R2=0.01) between SST and NDVI. This suggests that years with anomalously high SST do not significantly impact plant phenology. During the intense and long 2014/2015 MHW, peak NDVI values for ‘grass’ and ‘combined’ pixels were 2.0 and 1.7 standard deviations above the climatological average, while the shorter 2019/2020 MHW saw higher peaks of 3.2 and 2.4 standard deviations. However, the ‘grass’, ‘tree’ and ‘combined’ NDVI anomalies were statistically insignificant during both MHWs, showing that although NDVI appeared to increase during the shorter and less intense MHW, these values may be attributed to other factors. The data qualitatively suggest that MHW’s don’t impact the peak NDVI date, but more data at higher temporal resolution are necessary. Further research will involve analyzing fog indices and exploring confounding variables impacting NDVI, such as plant physiology, anthropogenic disturbance, and wildfires. In addition, it’s important to understand to what extent changes in NDVI are attributed to the driving factors of MHWs or the MHWs themselves. Ultimately, mechanistically understanding the impacts MHW intensity and duration have on terrestrial ecosystems will better inform coastal community resilience.
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Last Updated Nov 22, 2024 Related Terms
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By Space Force
Space Force officials have selected 14 senior master sergeants and 25 master sergeants for promotion in the 24S9 and 25S8 promotion cycles, respectively.
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By Space Force
The Department of the Air Force recorded significant audit achievements in Fiscal Year 2024, securing remediation's for all three of its audit roadmap targets, including two material weaknesses and one significant deficiency.
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By Space Force
The Department of the Air Force selected Schriever Space Force Base, Colorado, as the preferred and final location to host Space Delta 15.
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By NASA
JPL is a research and development lab federally funded by NASA and managed by Caltech. NASA/JPL-Caltech Workforce statement and memo to employees
JPL statement issued on Nov. 12, 2024:
While we have taken various measures to meet our current FY’25 budget allocation, we have reached the difficult decision to reduce the JPL workforce through layoffs. This reduction affects approximately 325 of our colleagues, an impact of about 5% of our workforce. The impacts are occurring across technical, business, and support areas of the Laboratory. These are painful but necessary adjustments that will enable us to adhere to our budget while continuing our important work for NASA and our nation.
The following is a memo sent earlier today from JPL Director Laurie Leshin to employees:
Dear Colleagues,
This is a message I had hoped not to have to write. I’m reaching out to share the difficult news that JPL will be taking a workforce action tomorrow, Nov. 13, resulting in a layoff of approximately 325 of our colleagues, or ~5% of our workforce. Despite this being incredibly difficult for our community, this number is lower than projected a few months ago thanks in part to the hard work of so many people across JPL. The workforce assessment conducted as part of this process has been both extensive and thorough, and although we can never have perfect insight into the future, I sincerely believe that after this action we will be at a more stable workforce level moving forward.
How we got here:
During our last town hall, I discussed our continued funding challenges and projections of what the potential impact on our workforce could look like. I shared that we had been working through multiple workforce scenarios to address the dynamic funding environment, and that we have been doing everything we can, in partnership with our colleagues at NASA and elsewhere, to minimize adverse effects on JPL’s capabilities and team.
Unfortunately, despite all these efforts, we need to make one further workforce reduction to meet the available funding for FY’25. This reduction is spread across essentially all areas of the Lab including our technical, project, business, and support areas. We have taken seriously the need to re-size our workforce, whether direct-funded (project) or funded on overhead (burden). With lower budgets and based on the forecasted work ahead, we had to tighten our belts across the board, and you will see that reflected in the layoff impacts.
As part of our workforce assessment and determining where reductions are being made, we have taken time to complete a full review of our competencies, future mission needs, and we have established guidance for our core capabilities across the Laboratory. We have worked closely with the Executive Council, division managers, project leadership and others to ensure we maintain the appropriate levels of technical expertise, capacity for innovation, and ability to deliver on an exciting future for JPL. Our focus will continue to be on empowering managers to support their teams through this action and equipping all of us with a variety of resources as we move forward together.
Here are the details about what will happen tomorrow:
Unless notified otherwise, all employees are required to work from home tomorrow Nov. 13, regardless of their telework status. Tomorrow you will be invited to a short, virtual, Lab-wide meeting with myself and Deputy Director Leslie Livesay at 9:30 a.m. We will relay the details of where we are in the process and what to expect. Please look out for the meeting notification that will follow this memo. There will not be organization-level notification meetings as in February. This one meeting will provide the information needed for the entire Lab at once.
Our approach is to prioritize notifying everyone via email as quickly as possible whether their role is being affected by the layoff or not. Then we can rapidly shift to providing personalized support to our laid-off colleagues who are part of the workforce reduction, including offering dedicated time to discuss their benefits, and several other forms of assistance. Because of system limitations, the individual email notifications will take place over several hours tomorrow. A schedule of the notifications, which will occur by organization, will be shared in the virtual briefing tomorrow morning and also posted on JPL Space, the JPL HR Website, and Slack. You can also find answers to Frequently Asked Questions (FAQs) on our website here.
Our JPL Community:
I know the absence of our colleagues will be acutely felt, especially after a very challenging year for the Lab. To those leaving JPL as a result of this action, we are grateful for your many vital contributions to JPL and to NASA. We will be here to support you during this time to ensure this transition is as smooth as possible.
To reiterate to you all, I believe this is the last cross-Lab workforce action we will need to take in the foreseeable future. After this action, we will be at about 5,500 JPL regular employees. I believe this is a stable, supportable staffing level moving forward. While we can never be 100% certain of the future budget, we will be well positioned for the work ahead. This may not help much in this difficult moment, but I do want to be crystal clear with my thoughts and perspective. If we hold strong together, we will come through this, just as we have done during other turbulent times in JPL’s nearly 90-year history. Finally, even though the coming leadership transition at NASA may introduce both new uncertainties and new opportunities, this action would be happening regardless of the recent election outcome.
While I know many of us are feeling anger or disappointment with this news, I encourage everyone to act with grace and empathy toward one another, and to lean on each other for support. I will be speaking with you again very soon to discuss our path ahead. Until then, know that we are an incredibly strong organization – our dazzling history, current achievements, and relentless commitment to exploration and discovery position us well for the future.
Laurie
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Last Updated Nov 12, 2024 Related Terms
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