This paper presents the results of one of the hydrological models, the InVEST “Annual Water Yield” (InVEST–AWY), applied to the Meta River basin in Colombia, which covers an area of 113,981 km². The study evaluates the performance of the model in different subbasins of the Meta River basin. The model’s accuracy was assessed using different statistical measures, including Nash–Sutcliffe Efficiency (NSE) coefficient, Root Mean Square Error (RMSE), correlation coefficients for the calibration (r_cal) and validation (r_val) periods. The overall performance of the model in the Meta River basin is relatively poor as indicated by the low NSE value of 0.07 and high RMSE value of 1071.61. In addition, the model explains only a 7% of the variance in the observed data. The sensitivity analysis revealed that a 30% reduction in crop coefficient (Kc) values would result in a 10.7% decrease in water yield. The model estimated, for example, the annual average water yield of the river in 2018 as 1.98 × 10¹¹ m³/year or 6273.4 m³/s, which is 1.3% lower than the reported value. The upper Meta River subbasin shows the highest NSE value (0.49), indicating a good result between observed and simulated water discharge. In contrast, the South Cravo River subbasin shows a negative NSE value of −1.29, indicating poor model performance. The Yucao River subbasin and the upper Casanare River subbasin also show lower NSE values compared to the upper Meta River subbasin, indicating less accurate model performance in these subbasins. The correlation coefficients in calibration (r_cal) and validation (r_val) for the upper Meta River, Yucao River, South Cravo River, and upper Casanare River subbasins were 0.79 and 0.83, 0.4 and 0.22, 0.5 and −0.25, and 0 and 0.18, respectively. These results provide useful insights into the limitations for the proper use of the InVEST–AWY model in Colombia. This study is the first to use the InVEST–AWY model on a large scale in the territory of Colombia, allowing to evaluate its effectiveness in hydrological modeling for water management.

The Arctic stratosphere winter season of 2021–2022 was characterized by a stable, cold stratospheric polar vortex with a volume of polar stratospheric clouds (PSC) close to the maximum values since 1980, before the beginning of minor sudden stratospheric warming (SSW) events in the late February and early March and major SSW on 20 March. Analysis of dynamical processes of the Arctic stratosphere using reanalysis data indicates that the main reasons for the strengthening of the stratospheric polar vortex in January–February are the minimum propagation of planetary wave activity from the troposphere to the stratosphere over the past 40 years and its reflection in the upper stratosphere–lower mesosphere in the second half of January. The first minor SSW was limited to the upper polar stratosphere, whereas the second one propagated to the middle and lower stratosphere and led to the disappearance of the PSC, which prevented significant ozone depletion. Both minor and major SSW events led to a weakening of the residual meridional circulation in the upper Arctic stratosphere and its intensification in the middle and lower stratosphere, which contributed to additional warming of the subpolar region and weakening of the polar vortex.

On the basis of simulations using a global climate model, the global and regional climate changes in the Holocene are estimated. According to our results, the average contemporary level of global near-surface temperature in recent decades exceeded the respective values during the last 10 kyr, including the period of the Holocene optimum (Middle Holocene, about 6 kyr B.P.). However, modern temperature regimes in particular regions (e.g., Europe) may be below the maximum warming level of the Middle Holocene. Global and regional climate changes and variations in the carbon cycle characteristics over the last century (based on model calculations, with the anthropogenic effect being taken into account) considerably differ from the variations in the preceding centuries and millennia, when natural impacts on the climate system played the key role.

The Arctic stratosphere winter season of 2020–2021 was characterized by a weakened stratospheric polar vortex as a result of a major sudden stratospheric warming (SSW) in early January. After the SSW, which persisted for about 3 weeks, and until the end of the winter season, the lower stratosphere temperature inside the stratospheric polar vortex remained higher than required for the formation of polar stratospheric clouds.

An analysis of spectra of wave disturbances with zonal wave numbers 1 ≤ k ≤ 10 is carried out using winter (November to March) ERA-Interim reanalysis geopotential data in the troposphere and...