The vertical number density of ozone from the ozone mapping and profiler suite (OMPS) limb measurements is firstly retrieved using wavelength pairing and multiplicative algebraic reconstruction technique. Our retrieved algorithm uses radiance in the visible (VIS) band to obtain ozone concentrations at altitudes of 12.5‒39.5 km, with a vertical resolution of 1 km. The results are compared with the OMPS/LP v2.6 ozone profile products provided by the national aeronautics and space administration (NASA), showing high consistency (<6%) between 16‒38 km. The correlation coefficient for the total ozone column in the stratosphere is 0.953. Using these retrievals, we investigate changes in stratospheric ozone concentration following the Tonga volcanic eruption and analyze the key physical and chemical processes affecting ozone concentration. The Tonga eruption releases a large amount of sulfate aerosols into the middle and lower stratosphere at 20°‒60°S. In mid-to-low latitudes of southern hemisphere, the enhanced sulfate aerosols increase ozone concentration in the middle stratosphere while reducing it in the lower stratosphere. Additionally, sulfate aerosols are transported through the Brewer‒Dobson (BD) circulation to Antarctica, where the enhanced Antarctic upwelling and polar stratospheric clouds (PSC) contribute to the enlargement of the polar ozone hole. Ozone plays a crucial role in the evolution of life on Earth. As an important trace gas in the atmosphere, ozone regulates the Earth’s climate, particularly in terms of temperature and energy distribution. Therefore, its concentration, distribution, and temporal evolution of ozone are closely related to research on ozone layer recovery, stratospheric circulation, and temperature response to increasing greenhouse gases. Therefore, obtaining daily global ozone profiles is crucial. In this study, we report the stratospheric ozone concentrations monitored by OMPS, validated against NASA’s OMPS/LP v2.6 products. Additionally, based on the retrievals, we analyze annual changes in stratospheric ozone before and after the Tonga submarine volcano eruption, as well as the chemical and kinetic mechanisms underlying these changes. This research is crucial for understanding how stratospheric ozone protects life on Earth from harmful ultraviolet radiation. We hope our research can provide a technical foundation for future data products from China’s space-based atmospheric remote sensing limb observations.

First, the limb radiances of the selected wavelengths are normalized to a reference tangent height that is insensitive to ozone. Using wavelength pairing, we retrieve ozone concentrations at different heights based on the variation in ozone’s absorption of solar radiance in the VIS band. Second, the SCIATRAN radiative transfer model is used to establish limb-simulated radiance. The observed and simulated radiances are transformed into retrieval vectors through radiance normalization and wavelength pairing, respectively. Finally, the multiplicative algebraic reconstruction technique (MART) algorithm is applied iteratively to correct and converge the ozone profile.

To verify our retrievals, we compare them with OMPS/LP v2.6 profiles provided by NASA. The retrieved ozone profiles are in good agreement with OMPS/LP v2.6, with high consistency in structure, peak height, and size [Fig. 5(a)], and a deviation of less than 2% between 18‒31 km [Fig. 5(b)]. The tropical profiles also show good consistency [Fig. 6(a)], with deviations of less than 10% across six latitude bands between 15‒38 km, except for the southern latitude band [Fig. 6(b)]. In addition, the total ozone column in the stratosphere shows a correlation coefficient of 0.953 with OMPS/LP v2.6 (Fig. 7). The retrievals from September 1, 2021, September 1, 2022, and September 1, 2023, are highly consistent with the global map of OMPS/LP v2.6 ozone concentrations (Fig. 8). Based on our data, we compare ozone concentrations on September 1, October 1, and November 16 from 2021 to 2023 (Fig. 9). We find that in mid-to-low latitudes, the abundance of active nitrogen in the stratosphere decreases due to sulfate aerosols formed after the Tonga volcanic eruption, leading to an increase in ozone concentration in the middle stratosphere. Sulfate aerosols also weaken solar radiation, resulting in negative ozone anomalies in the lower stratosphere. These aerosols are transported southward by the BD circulation, causing significant ozone loss in the lower polar stratosphere (60°S). After over a year of sedimentation, total ozone columns in mid-to-high latitudes of the southern hemisphere recover in 2023 (Fig. 11).

In this study, we use wavelength pairing and the MART algorithm to retrieve the stratospheric ozone profiles from OMPS limb measurements. Our retrievals are validated against OMPS/LP v2.6 products provided by NASA, showing good consistency. Additionally, we analyze the influence and mechanisms of the Tonga submarine volcanic eruption on stratospheric ozone before and after the event. Our results demonstrate the effectiveness of wavelength pairing and MART in retrieving OMPS/LP ozone profiles, providing a solid technical foundation for future applications. However, studying stratospheric ozone recovery requires long-term, consistent datasets, and using the same retrieval scheme is critical in minimizing discrepancies between different satellite data.