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NASA NTRS1988

The Nimbus 7 LIMS (Limb Infrared Monitor of the Stratosphere) water vapor measurements

Earth orbital instruments, designed to measure the vertical and spatial distribution of atmospheric water vapor is discussed. Specifically, the operation of the Limb Infrared Monitor of the Stratosphere (LIMS) experiment is examined. The LIMS is a six channel limb scanning radiometer that was launched aboard Nimbus 7 in 1978. Profiles of stratospheric and mesospheric temperature, water vapor, and various other constituents were obtained by inverting the LIMS radiance measurements. This same technique was used in 1981 to analyze the data returned from another limb scanning radiometer aboard the Solar Mesosphere Explorer.

Remsberg, Ellis E.↗
NASA NTRS2010

LIMS Version 6 Level 3 Dataset

This report describes the Limb Infrared Monitor of the Stratosphere (LIMS) Version 6 (V6) Level 3 data products and the assumptions used for their generation. A sequential estimation algorithm was used to obtain daily, zonal Fourier coefficients of the several parameters of the LIMS dataset for 216 days of 1978-79. The coefficients are available at up to 28 pressure levels and at every two degrees of latitude from 64 S to 84 N and at the synoptic time of 12 UT. Example plots were prepared and archived from the data at 10 hPa of January 1, 1979, to illustrate the overall coherence of the features obtained with the LIMS-retrieved parameters.

Remsberg, Ellis E.↗
NASA NTRS2021

Residual Temperature Bias Effects in Stratospheric Species Distributions from LIMS

The Nimbus 7 Limb Infrared Monitor of theStratosphere (LIMS) instrument operated from 25 Octo-ber 1978 through 28 May 1979. Its version 6 (V6) profileswere processed and archived in 2002. We present severaldiagnostic examples of the quality of the V6 stratospheric species distributions based on their level 3 zonal Fourier co-efficient products. In particular, we show that there are smalldifferences in the ascending (A) minus descending (D) or-bital temperature–pressure orT(p) profiles (theirA−Dval-ues) that affect (A−D) species values. SystematicA−Dbi-ases inT(p) can arise from small radiance biases and/or fromviewing anomalies along orbits. There can also be (A−D)differences inT(p) due to not resolving and correcting forall of the atmospheric temperature gradient along LIMS tan-gent view-paths. An error inT(p) affects species retrievalsthrough (1) the Planck blackbody function in forward calcu-lations of limb radiance that are part of the iterative retrievalalgorithm of LIMS, and (2) the registration of the measuredLIMS species radiance profiles in pressure altitude, mainlyfor the lower stratosphere. There are clearA−Ddifferencesfor ozone, H2O, and HNO3but not for NO2. Percentage differences are larger in the lower stratosphere for ozone andH2O because those species are optically thick. We evaluateV6 ozone profile biases in the upper stratosphere with the aid of comparisons against a monthly climatology of UV–ozone soundings from rocketsondes. We also provide resultsof time series analyses of V6 ozone, H2O, and potential vor-ticity for the middle stratosphere to show that their average(A+D) V6 level 3 products provide a clear picture of the evolution of those tracers during Northern Hemisphere win-ter. We recommend that researchers use the average V6 level3 product for their science studies of stratospheric ozone andH2O, while keeping in mind that there are uncorrected non-local thermodynamic equilibrium effects in daytime ozone inthe lower mesosphere and in daytime H2O in the uppermoststratosphere. We also point out that the present-day Soundingof the Atmosphere using Broadband Emission Radiometry(SABER) experiment provides measurements and retrievalsof temperature and ozone that are nearly free of anomalousdiurnal variations and of effects from gradients at low and middle latitudes.

Ellis Remsberg↗
DOE OSTI2023

Autoregulation of the LIM kinases by their PDZ domain

LIM domain kinases (LIMK) are important regulators of actin cytoskeletal remodeling. These protein kinases phosphorylate the actin depolymerizing factor cofilin to suppress filament severing, and are key nodes between Rho GTPase cascades and actin. The two mammalian LIMKs, LIMK1 and LIMK2, contain consecutive LIM domains and a PDZ domain upstream of the C-terminal kinase domain. The roles of the N-terminal regions are not fully understood, and the function of the PDZ domain remains elusive. Here, we determine the 2.0 Å crystal structure of the PDZ domain of LIMK2 and reveal features not previously observed in PDZ domains including a core-facing arginine residue located at the second position of the ‘x-Φ-G-Φ’ motif, and that the expected peptide binding cleft is shallow and poorly conserved. We find a distal extended surface to be highly conserved, and when LIMK1 was ectopically expressed in yeast we find targeted mutagenesis of this surface decreases growth, implying increased LIMK activity. PDZ domain LIMK1 mutants expressed in yeast are hyperphosphorylated and show elevated activity in vitro. This surface in both LIMK1 and LIMK2 is critical for autoregulation independent of activation loop phosphorylation. Overall, our study demonstrates the functional importance of the PDZ domain to autoregulation of LIMKs.

59 BASIC BIOLOGICAL SCIENCES↗
NASA NTRS1982

LIMS Instrument Package (LIP) balloon experiment: Nimbus 7 satellite correlative temperature, ozone, water vapor, and nitric acid measurements

The Limb Infrared Monitor of the Stratosphere (LIMS) LIP balloon experiment was used to obtain correlative temperature, ozone, water vapor, and nitric acid data at altitudes between 10 and 36 kilometers. The performance of the LIMS sensor flown on the Nimbus 7 Satellite was assessed. The LIP consists of the modified electrochemical concentration cell ozonesonde, the ultraviolet absorption photometric of ozone, the water vapor infrared radiometer sonde, the chemical absorption filter instrument for nitric acid vapor, and the infrared radiometer for nitric acid vapor. The limb instrument package (LIP), its correlative sensors, and the resulting data obtained from an engineering and four correlative flights are described.

Lee, R. B., III↗
NASA NTRS1982

Results from the LIMS experiment for the PMP-1 winter 1978/79

The results of a preliminary analysis of the data on the global distributions of temperature and trace constituents in the middle atmosphere (15-65 km) obtained with the limb IR monitor (LIMS) are presented. The 6-channel limb-scanning radiometer was sensitive to the 15 micron bands of CO2, as well as other wavelengths, and was launched on the Nimbus 7 satellite in 1978. The derived data were partially compared with Soviet rocketsonde data to track an evolution in a warming trend over Siberia. The morphology of the changes were attributed to stratospheric warming. The comparisons with rocketsonde data indicated that the LIMS data were suitable for the determination of planetary wave amplitudes and phases, heat and momentum transport, and Eliassen-Palm fluxes.

Gille, J. C.↗
NASA NTRS1982

The variability of stratospheric nitrogen compounds observed by LIMS in the winter of 1978-1979

The LIMS experiment was launched on the Nimbus 7 satellite for the purpose of sounding the vertical structure of temperature and key upper atmosphere trace gases on a global scale. The technique of thermal infrared limb sounding was used to obtain measurements of O3, H2O, NO2, and HNO3. LIMS collected data almost continuously from late October to late May over the latitude range from 64 deg S to 84 deg N. Two of the gases, NO2 and HNO3, are important elements in the NO(x) chain of chemical reactions leading to ozone destruction. Results for these gases are described in terms of zonal mean profiles and latitudinal distributions. The period selected for study is January-May 1979, when a major stratospheric warming occurred.

Russell, J. M., III↗
NASA NTRS1984

Evidence for equatorial Kelvin modes in Nimbus-7 LIMS

Equatorial Kelvin waves have emerged as an important source of westerly momentum for the tropical stratosphere. The present investigation is concerned with an analysis of remotely derived temperatures from Nimbus-7 LIMS (Limb Infrared Monitor of the Stratosphere). It is found that eastward propagating disturbances are present in two independent LIMS data sets. The disturbances manifest themselves consistently at several levels throughout the stratosphere and account for much of the tropical temperature variance out to latitudes where extratropical signals become large. Compelling evidence is found for several distinct phase velocities. Spectral analysis indicates isolated eastward variance at principally two frequencies for both wavenumbers.

Salby, M. L.↗
NASA NTRS1984

Validation of nitrogen dioxide results measured by the limb infrared monitor of the stratosphere (LIMS) experiment on NIMBUS 7

The validation of results from the nitrogen dioxide channel and the quality of the data are examined in connection with the LIMS experiment which ran from late October 1978 to late May 1979. Factors studied include: channel characteristics, experiment errors due to instrument and spacecraft effects, predicted and measured precision, predicted accuracy, and comparisons with correlative measurements made in a series of balloon underflights. Features such as profile shape and slope of the mixing ratio altitude distribution are in good agreement. The LIMS data also fall within the range of previous mixing ratio measurements and are consistent with model estimates. The calculated on-orbit precision is about 0.3 ppbv and the estimated accuracy from simulations is about 2 ppbv over the 3-10-mbar range. Accuracy is less at higher and lower pressure levels. These results provide the first day-night set of nitrogen dioxide measurements from space.

Russell, J. M., III↗
NASA NTRS1984

Spectroscopy and transmittances for the LIMS experiment

The Limb Infrared Monitor of the Stratosphere (LIMS) instrument on the Nimbus 7 spacecraft sensed limb emission profiles for 7 months, starting in October 1979. Vertical temperature profiles are inferred from measurements in two CO2 channels, and constituent profiles are obtained form the O3, HNO3, NO2, and water vapor channels. The line parameters used to calculate transmittances in the retrieval algorithm are presented. Their adequacy for LIMS and for other applications are assessed, and recommendations for future investigations are outlined.

Drayson, S. R.↗
NASA NTRS1985

Comparison of horizontal winds from the LIMS satellite instrument with rocket measurements

Statistical results are given for a comparison between horizontal geostrophic winds computed from satellite height data and all available in situ rocket wind soundings during a 7-month period. The satellite data are the daily mapped fields from the Nimbus 7 Limb Infrared Monitor of the Stratosphere (LIMS) instrument, which extend from 100 to 0.1 mbar. Results indicate that in both the tropics and the extratropical Northern Hemisphere, the average zonal and meridional wind speeds agree to within 2-4 m/s throughout the stratosphere. The rms differences are much larger, with values of 5-10 m/s in the lower stratosphere, increasing to 20-40 m/s in the lower mesosphere. Time series show that LIMS and rocketsonde zonal wind speeds show coherent variations with temporal periods of 1-2 weeks and more, and both exhibit irregular variations on time scales of less than one week.

Smith, A. K.↗
NASA NTRS1985

Diurnal tide in the equatorial middle atmosphere as seen in LIMS temperatures

The distribution of day-night temperature differences in the middle atmosphere determined by the Nimbus 7 LIMS experiment is described. Day-night differences maximize at and are approximately symmetric about the equator. Successive centers of opposite sign increase in amplitude with altitude, the pattern having a vertical wavelength of approximately 25 km. Profiles of rocket meridional wind at Kwajalein (8.7 deg N) and Ascension Island (8.0 deg S) taken near local noon and averaged over the LIMS data period, exhibit maxima which support the tidal interpretation of the equatorial temperature pattern. These characteristics are in general agreement with previous observational and theoretical results for the solar driven diurnal tide. Substantial time variations in amplitude and in location of the temperature maxima are observed. The diurnal tide near the equatorial stratopause appears to be influenced by the phase of the semiannual oscillation.

Hitchman, M. H.↗
NASA NTRS1985

The integrated enstrophy budget of the winter stratosphere diagnosed from LIMS data

The quasi-geostrophic integrated enstrophy budget for the 1978 to 1979 winter has been analyzed from 10-0.1 mb using LIMS data. During January and late February periods a significant imbalance in the budget appears at 10mb. This imbalance is attributed to Rossby wave breaking. It is produced by the irreversible transfer of enstrophy to smaller scales not resolved by LIMS. The imbalance episodes correspond well to the appearance of Ertel vorticity filaments shown by McIntyre and Palmer (1984). From a seasonal viewpoint, the integrated enstrophy shows an average (although irregular) transfer from a zonal mean reservoir to waves which are then dissipated. On a shorter time scale the integrated enstrophy sloshes back and forth between the waves and mean flow in early winter; then, beginning with the January sudden warming, the total enstrophy is reduced more rapidly. Between 10 mb and 1 mb this reduction is more or less continuous until the end of February. However, in the mesosphere the total enstrophy decrease is very short lived, being quickly restored after the January warming. Even though the zonal mean integrated enstrophy is large, only about 10% can be utilized by the waves. The available integrated potential enstrophy is introduced, which is a better measure of how close the flow is to saturation by Rossby waves. The largest amount of available potential enstrophy in early January is at 1 mb with decreasing amounts above and below. Saturation of the flow by Rossby waves occurs below 1 mb only coincident with sudden warmings; however, at mesospheric heights the flow appears to be nearly saturated throughout the winter.

Schoeberl, M. R.↗
NASA NTRS1986

Description of data on the Nimbus 7 LIMS map archive tape: Ozone and nitric acid

The Nimbus 7 Limb Infrared Monitor of the Stratosphere (LIMS) data set has been processed into a Fourier coefficient representation with a Kalman filter algorithm applied to profile data at individual latitudes and pressure levels. The algorithm produces synoptic data at noon Greenwich Mean Time (GMT) from the asynoptic orbital profiles. This form of the data set is easy to use and is appropriate for time series analysis and further data manipulation and display. Ozone and nitric acid results are grouped together in this report because the LIMS vertical field of views (FOV's) and analysis characteristics for these species are similar. A comparison of the orbital input data with mixing ratios derived from Kalman filter coefficients indicates errors in mixing ratio of generally less than 5 percent, with 15 percent being a maximum error. The high quality of the mapped data was indicated by coherence of both the phases and the amplitudes of waves with latitude and pressure. Examples of the mapped fields are presented, and details are given concerning the importance of diurnal variations, the removal of polar stratospheric cloud signatures, and the interpretation of bias effects in the data near the tops of profiles.

Remsberg, E. E.↗
NASA NTRS1988

Analysis of LIMS data by potential vorticity inversion

This paper analyzes LIMS data for a minor warming of January 1979 by potential vorticity inversion, to investigate how flows in the middle atmosphere were determined. The inversion problem of calculating the flow from the potential vorticity is solved repeatedly, including and excluding different portions of the potential vorticity, thus revealing which bits of potential vorticity were important in determining the flow at a time and location of interest. The results of the analysis of LIMS data indicate that the middle stratospheric flow is dominated by potential vorticity that is local in height and in latitude, while planetary-scale mesospheric flows are primarily induced by potential vorticity in the stratosphere. A possible explanation for this difference is proposed.

Robinson, Walter A.↗
NASA NTRS1989

The mean ozone profile and its temperature sensitivity in the upper stratosphere and lower mesosphere - An analysis of LIMS observations

Multiple simultaneous LIMS (Limb Infrared Monitor of the Stratosphere) observations of both O3 and temperature T in the upper stratosphere and lower mesosphere are analyzed to derive O3-T correlations for comparisons with model calculations. The zonally averaged O3 profile is compared with results from a simplified photochemical model that assumes O3 to be in a photochemical steady state. The model profile is systematically lower than the observed profile. Key parameters are identified in which changes can systematically increase the O3 profile in both the stratosphere and the mesosphere. The LIMS-derived values for the sensitivity of O3 to changes in T are compared with equilibrium model calculations which include the T-driven opacity feedback effect on photodissociation rate constants. The theoretical O3 response to temperature perturbations is investigated. It is shown how the O3-T sensitivity coefficient is affected by zonal and vertical advection terms as well as by the photochemical coupling between O3 and T.

Froidevaux, Lucien↗
NASA NTRS1991

LIMS (Limb Infrared Monitor of the Stratosphere) observation of traveling planetary waves and potential vorticity advection in the stratosphere and mesosphere

Eastward and westward traveling waves were observed by the Nimbus 7 Limb Infrared Monitor of the Stratosphere (LIMS) during the northern winter 1978-1979. Eastward waves were prevalent in early winter and were involved in a minor Canadian warming in December 1978. A large westward traveling wave, as described by previous authors, was observed in January 1979 during a series of minor warmings. By comparing these two events, it is shown that in both cases the superposition of traveling and quasi-stationary waves led to constructive interference that was responsible for the warmings. However, there was significant asymmetry between eastward and westward traveling components. A local Eulerian analysis of potential vorticity (PV) transport indicates that adiabatic, geostrophic advection by the resolvable scales of motion explains qualitatively (but not quantitatively) the observed potential vorticity tendencies in the LIMS Northern Hemisphere winter. In particular, calculated advection explains the eastward rotation of the main vortex, intrusion of low PV air into the polar cap, and formation of high PV filaments at the vortex periphery.

Dunkerton, Timothy J.↗
NASA NTRS1994

Effect of the HITRAN 92 spectral data on the retrieval of NO2 mixing ratios from Nimbus 7 LIMS

To ensure spectral consistency when comparing Nimbus 7 Limb Infrared Monitor of the Stratosphere Experiment (LIMS) NO2 distributions with those from Atmosphere Trace Molecule Spectroscopy (ATMOS) and Upper Atmosphere Research Satellite Experiments (UARS), 1 day (May 5, 1979) of LIMS measurements were reprocessed using the NO2 line list on the HITRAN 92 tape compiled by the Airforce Geophysics Laboratory (AFGL). The revised NO2 mixing ratios are smaller by up to 20%. The decrease is not constant with height, latitude, or time of day but depends on the absolute amount of NO2 in the profile, as a result of a change in the degree of saturation for the strong NO2 spectral lines. The revised NO2 agrees better with correlative measurements and with NO2 distributions from the Stratospheric Aerosol and Gas Experiment (SAGE) and Halogen Occultation Experiment (HALOE) satellite experiments but not with those from ATMOS 85. Profiles of the day/night ratio of revised NO2 are now larger near 5 hPa. There is also some improvement between observed and modeled ozone in the upper stratosphere, when the revised nighttime NO2 profile is used as the estimate of NO(y) for the model calculations.

Remsburg, Ellis E.↗