Jing Feng

Princeton University | PU · Department of Geosciences

Measuring atmospheric conditions above convective storms using spaceborne instruments is challenging. The operational retrieval framework of current hyperspectral infrared sounders adopts a cloud-clearing scheme that is unreliable in overcast conditions. To overcome this issue, previous studies have developed an optimal estimation method that retri...

The tropical tropopause layer (TTL) is the transition layer between the troposphere and the stratosphere. Tropical cyclones may impact the TTL by perturbing the vertical distributions of cloud, temperature, and water vapor. This study combines several A-Train instruments, including radar from CloudSat, lidar from the Cloud-Aerosol Lidar and Infrare...

In a warming climate, greenhouse gases modulate thermal cooling to space from the surface and atmosphere, which is a fundamental feedback process that affects climate sensitivity. Recent studies have found that when relative humidity (RH) is constant with global warming, Earth's clear‐sky longwave feedback would be dominated by surface cooling to s...

The Earth's global radiation budget depends critically on the relationship between outgoing longwave radiation (OLR) and surface temperature (Ts). Using the ERA5 reanalysis dataset, we find that although OLR appears to be linearly dependent on Ts over a wide range, there are significant deviations from the linearity in the OLR-Ts relationship for r...

In this study, a novel optics scheme for cloud and precipitation modeling is introduced. Based on the Mie theory and existing datasets on ice crystals, the scheme offers an open-source package for generating data for user-defined gas bands, particle size distributions, and crystal habits. This approach ensures continuity across wide spectral bands...

In this study, we examine the spatial pattern of the surface amplification factor (SAF). SAF corresponds to the surface element of the energy gain kernel derived in Part I of this three-part series papers, representing the amplification rate of input energy perturbations at the surface. At a given location, SAF amplifies surface energy perturbation...

This paper introduces a climate feedback kernel, referred to as the “energy gain kernel” (EGK). EGK allows for separating the net longwave radiative energy perturbations given by a Planck feedback matrix explicitly into thermal energy emission perturbations of individual layers, and thermal radiative energy flux convergence perturbations at individ...

The Earth’s global radiation budget depends critically on the relationship between outgoing longwave radiation (OLR) and surface temperature (Ts). Above 270 K, which represents 89% of the surface of Earth, we find that linearity poorly represents the OLR-TS relationship. Although the AMIP runs of CMIP6 models largely capture the linearity of OLR an...

Deep convective overshooting has been shown to transport water vapor into the midlatitude lower stratosphere. However, it has not been demonstrated how the convective water vapor plumes evolve after the overshoots collapse. Furthermore, there is a lack of characterization of the convective water vapor plumes, nor is it clear whether satellite instr...

Greenhouse gases (GHGs) are gases that absorb and emit thermal energy. In a warming climate, GHGs modulate the thermal cooling to space from the surface and atmosphere, which is a fundamental feedback process that affects climate sensitivity. Previous studies have stated that the thermal cooling to space with global warming is primarily emitted fro...

Greenhouse gases (GHGs) are gases that absorb and emit thermal energy. In a warming climate, GHGs modulate the thermal cooling to space from the surface and atmosphere, which is a fundamental feedback process that affects climate sensitivity. Previous studies have stated that the thermal cooling to space with global warming is primarily emitted fro...

The tropical tropopause layer (TTL) is the transition layer between the troposphere and the stratosphere. Tropical cyclones may impact the TTL by perturbing the vertical distributions of cloud, temperature, and water vapor, although this impact is poorly quantified due to the lack of collocated data. To address this problem, we implement a synergis...

Measuring atmospheric conditions above convective storms is challenging. This study finds that the uncertainties in cloud properties near the top of deep convective clouds have a non-negligible impact on the TOA infrared radiances which cannot be fully eliminated by adopting a slab-cloud assumption. To overcome this issue, a synergetic retrieval me...

Accurate integration of directional radiance shows that the conventional diffusivity-factor approximation with a constant diffusivity angle results in an overestimation of the outgoing longwave radiation (OLR) in the window band and an underestimation in the absorption band. We propose an analytical estimation of a spectrally dependent diffusivity...

This study examines the feasibility of retrieving lower-stratospheric water vapor using a nadir infrared hyperspectrometer, with the focus on the detectability of small-scale water vapor variability. The feasibility of the retrieval is examined using simulation experiments that model different instrument settings. These experiments show that the in...