Conclusion:
This study presented a method that integrated future climate and land
use projection with a hydrologic model to investigate the water balance
under combined effect of climate change and land use change. To address
some level of the uncertainty with the approach we used three CMIP5 GCM
outputs under two emission scenarios (RCP4.5 and RCP6.0). the future
time period was split in two time period (mid-century and late-century).
Calibration and sensitivity analyses were carried out to make sure the
hydrologic model output is reliable. Results show increase in
temperature and precipitation in UCS. Annual maximum and minimum
temperature are projected to increase up to 30% especially during
Summer and Winter. Rainfall will also increase by around 11%, however
different emission scenarios showed different trend through the
simulation period. surface runoff, water yield, and discharge at the two
stations were estimated to increase. However, surface runoff changes
were the largest. Increases in discharge during Summer and Fall are more
extreme than other seasons. ET has the modest changes and is expected to
decrease. This study can be helpful as an example for areas that mainly
comprised of forest and agricultural cover. Additionally, this study can
provide information for investigating how future climate data and land
use projections could impact hydrological processes. In Southeastern
watersheds. This region has not been under focus for climate and land
use management studies. Moreover, data and results shown here can
provide help in sustainable management especially for Native American
Reservations located within Upper Choctawhatchee subbasin. The model
used here, showed satisfactory performance that can be further used to
study best management practices, water quality modelling (NPS and PS
pollution) and also to track extreme weather footprint such as hurricane
and tropical storms, and droughts which have been more frequent
recently.