52 research outputs found
Investigation of cloud/water vapor motion winds from geostationary satellite
Work has been primarily focussed on three tasks: (1) comparison of wind fields produced at MSFC with the CO2 autowind/autoeditor system newly installed in NESDIS operations; (2) evaluation of techniques for improved tracer selection through use of cloud classification predictors; and (3) development of height assignment algorithm with water vapor channel radiances. The contract goal is to improve the CIMSS wind system by developing new techniques and assimilating better existing techniques. The work reported here was done in collaboration with the NESDIS scientists working on the operational winds software, so that NASA funded research can benefit NESDIS operational algorithms
2014 AMV intercomparison study report (comparison of NWC SAF/HRW AMVswith AMVs from other producers)
Previous Atmospheric Motion Vector (AMV) intercomparison studies, conducted from 2007 to 2009, compared the operational AMV algorithms of various satellite-derived wind producers using a common set of MSG/SEVIRI images and ancillary data. The studies assessed how the cloudy AMVs from the unique wind producers compared in terms of coverage, speed, direction, and cloud height
(Genkova et al. 2008; Genkova et al. 2010).
The goal of this new study is to:
· Include the NWC SAF/HRW algorithm in the intercomparison study in order to quantify its performance relative to the other AMV algorithms.
· Update the results of the previous AMV intercomparison studies because many of the operational AMV algorithms have changed since the last study.
· Perform follow up studies as identified in the previous intercomparison work, such as considering specific characteristics of the input data and AM
A new atmospheric motion vector intercomparison study
Ponencias presentadas en: 12th International Winds Workshop, Copenhagen, Denmark (15-20 June 2014)This study furthers a line of previously completed research regarding the similarities and differences between the operational Atmospheric Motion Vector (AMV) algorithms of various satellite-derived wind producers. By using a common set of MSG/SEVIRI images and ancillary data, past intercomparison studies assessed how the cloudy AMVs from each unique wind producer compared in terms of coverage, speed, direction, and cloud height (Genkova et al. 2008; Genkova et al. 2010). The current study focuses on including the CMA and NWC SAF AMV algorithms in the intercomparison in order to quantify its performance relative to other AMV algorithms, on updating the results of the previous AMV intercomparison studies due to the changes that have occurred since 2009, and lastly, on performing follow up studies, identified in the previous intercomparison work, to analyze particular issues in pursuance of a more complete understanding of how the different AMV algorithms compare
A New Tropical Cyclone Dynamic Initialization Technique Using High Temporal and Spatial Density Atmospheric Motion Vectors and Airborne Field Campaign Data
Background: Initialization of tropical cyclones in numerical weather prediction (NWP) systems is a great challenge: Mass-wind eld balance; Secondary circulation and heating; Asymmetries. There can be large adjustments in structure and intensity in the rst 24 hours if the initial vortex is not in balance: Spurious gravity waves; Spin-up (model and physics). Existing mesoscale NWP model TC (Tropical Cyclone) initialization strategies: Bogus vortex, cold start from global analyses; 3DVAR or 4DVAR, possibly with synthetic observations; EnKF (Ensemble Kalman Filter); Dynamic initialization. Dynamic initialization allows vortex to have improved balance and physics spin-up at the initial time (e.g., Hendricks et al. 2013, 2011; Nguyen and Chen 2011; Fiorino and Warner 1981; Hoke and Anthes 1976). Himawari-8 geostationary satellite has capability of continuous imagery (10-minutes) over the full disk: New GOES-R satellites will have same capability. This will allow for unprecedented observations of tropical cyclones. However, current data assimila1on systems are not capable of ingesting such high temporal observations (Atmospheric Mo1on Vectors - AMVs). Hourly AMVs are produced, and thinned to 100-kilometer spacing in the horizontal. An entirely new data assimilation concept is required to utilize these observations
Analysis of High Temporal and Spatial Observations of Hurricane Joaquin During TCI-15
Objectives: Provide an example of why analysis of high density soundings across Hurricane Joaquin also require highly accurate center positions; Describe technique for calculating 3-D zero-wind center positions from the highly accurate GPS positions of sequences of High-Density Sounding System (HDSS) soundings as they fall from 10 km to the ocean surface; Illustrate the vertical tilt of the vortex above 4-5 km during two center passes through Hurricane Joaquin on 4 October 2015
Impacts of woodland planting on nature-based recreational tourism in upland England: a case study
Upland landscapes provide important ecosystem services (ES) to society. One cultural ES– nature-based recreational tourism (NBR) – is a growing industry in upland regions that provides an important revenue to areas where other industries are often in decline. NBR tourism is a service that relies partly on the aesthetic appearance of the landscape and changes in land management, such as increasing woodland cover, changes the appearance of the landscape and may therefore have a positive or negative impact on the economic value generated by NBR tourism. We tested this query, by carrying out a survey of NBR tourists, using photo visualisation of different woodland scenarios, in a pastoral upland landscape in a UK National Park. This was conducted to estimate the economic value of NBR tourism under different woodland scenarios and participant’s preferences. The findings presented in this paper suggest that NBR tourism generates a substantial income to the area and that the economic value would not decrease, if woodland cover were to increase up to 75%. The findings also make an important observation on how there is a difference between peoples’ preference for woodland levels and the probability of return visits
Weather Avoidance Guidelines for NASA Global Hawk High-Altitude Unmanned Aircraft Systems (UAS)
The current Global Hawk flight rules would probably not have been effective in the single event of greatest concern (the Emily encounter). The cloud top had not reached 50,000 ft until minutes before the encounter. The TOT and lightning data would not have been available until near the overflight time since this was a rapidly growing cell. This case would have required a lastminute diversion when lightning became frequent. Avoiding such a cell probably requires continual monitoring of the forward camera and storm scope, whether or not cloud tops have been exceeding specific limits. However, the current overflight rules as strictly interpreted would have prohibited significant fractions of the successful Global Hawk overpasses of Karl and Matthew that proved not to be hazardous. Many other high altitude aircraft (ER2 and Global Hawk) flights in NASA tropical cyclone field programs have successfully overflown deep convective clouds without incident.The convective cell that caused serious concern about the safety of the ER2 in Emily was especially strong for a tropical cyclone environment, probably as strong or stronger than any that was overflown by the ER2 in 20 previous flights over tropical cyclones. Specifically, what made that cell a safety concern was the magnitude of the vertical velocity of the updraft, at least 20 m/s (4000 ft/minute) at the time the ER2 overflew it. Such a strong updraft can generate strong gravity waves at and above the tropopause, posing a potential danger to aircraft far above the maximum altitude of the updraft itself or its associated cloud top. Indeed, the ER2 was probably at least 9000 ft above that cloud top. Cloudtop height, by itself, is not an especially good indicator of the intensity of convection and the likelihood of turbulence. Nor is overflying high cloud tops (i.e. > 50,000 ft) of particular concern unless there is other evidence of very strong convective updrafts beneath those tops in the path of the aircraft. center dot Lightning, especially lightning with a high flash rate, is well correlated with convective intensity. Lightning with a minimal flash rate (say 13 flashes per minute) is indicative of updraft speeds of about 10 m/s in the mixed phase region where charge is being separated, generally at altitudes about 2025 kft in a hurricane. That is still stronger than typical updrafts (more like 5 m/s). An unresolved issue is whether there is a high and instantaneous correlation between vertical velocity in the middle troposphere (necessary for lightning generation) and near cloud top (more direct concern for overflights)
Applications of NASA TROPICS Data for Tropical Cyclone Analysis, Nowcasting, and Impacts
No abstract availabl
Targeting macrophage Histone deacetylase 3 stabilizes atherosclerotic lesions
Macrophages are key immune cells found in atherosclerotic plaques and critically shape atherosclerotic disease development. Targeting the functional repertoire of macrophages may hold novel approaches for future atherosclerosis management. Here, we describe a previously unrecognized role of the epigenomic enzyme Histone deacetylase 3 (Hdac3) in regulating the atherosclerotic phenotype of macrophages. Using conditional knockout mice, we found that myeloid Hdac3 deficiency promotes collagen deposition in atherosclerotic lesions and thus induces a stable plaque phenotype. Also, macrophages presented a switch to anti-inflammatory wound healing characteristics and showed improved lipid handling. The pro-fibrotic phenotype was directly linked to epigenetic regulation of the Tgfb1 locus upon Hdac3 deletion, driving smooth muscle cells to increased collagen production. Moreover, in humans, HDAC3 was the sole Hdac upregulated in ruptured atherosclerotic lesions, Hdac3 associated with inflammatory macrophages, and HDAC3 expression inversely correlated with pro-fibrotic TGFB1 expression. Collectively, we show that targeting the macrophage epigenome can improve atherosclerosis outcome and we identify Hdac3 as a potential novel therapeutic target in cardiovascular disease
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