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paper.md

@@ -67,7 +67,7 @@ bibliography: paper.bib
 
 # Introduction
 
-GRACE stands for the Gravity Recovery and Climate Experiment, a joint satellite mission by the National Aeronautics and Space Administration (`NASA`) in the USA, and the Geoforschung Zentrum (`GFZ`) in Germany. GRACE mission launced on 17 March, 2002, and ended on 27 October, 2017. Some details of the GRACE mission are provided in `Table 1`. GRACE has a successor, GRACE-FO, which was successfully launched on 22 May 2018 and is currently operational. GRACE consists of two identical satellites in the same orbit separated by approx. 220 km. The mission measures changes in the intersatellite distance with a microwave ranging system that gives an accuracy in the range of micrometers `[@wahr1998time:1998]`. When the satellite system comes in the vicinity of a temporal mass anomaly, the relative intersatellite distance changes and it can be inverted to estimate the mass change near the surface of the Earth. Over the continental land surface, the hydrological processes are the major driver of the variation in mass anomaly at monthly to decadal scales. However various other signals such as oceanic and atmospheric variations, high frequency tidal mass changes, systemic correlated errors, etc. are also part of the obtained GRACE signals `[@humphrey2023using:2023]`. Some of the unwanted signals, such as the high frequency tidal mass changes in the ocean and the atmosphere, are modelled and removed at level 1 processing `(Flechtner, 2007)`, while noise is still present at level 2 and it requires filtering `[@wahr1998time:1998; @vishwakarma2017understanding:2016]`. The choice of filter and/or subsequent steps to counter the signal loss due to filtering have an impact on the quality of GRACE products that are of interest to hydrologists `(Humphrey et al., 2023; Vishwakarma, 2020)`. The estimated hydrological signal is represented in terms of  `total water storage anomaly` (`TWSA`), which is the change in the water mass over a vertical column. Conventionally, it is represented in terms of `equivalent water height` (`m`). <br>
+GRACE stands for the Gravity Recovery and Climate Experiment, a joint satellite mission by the National Aeronautics and Space Administration (`NASA`) in the USA, and the Geoforschung Zentrum (`GFZ`) in Germany. GRACE mission launced on 17 March, 2002, and ended on 27 October, 2017. Some details of the GRACE mission are provided in `Table 1`. GRACE has a successor, GRACE-FO, which was successfully launched on 22 May 2018 and is currently operational. GRACE consists of two identical satellites in the same orbit separated by approx. 220 km. The mission measures changes in the intersatellite distance with a microwave ranging system that gives an accuracy in the range of micrometers [@wahr1998time]. When the satellite system comes in the vicinity of a temporal mass anomaly, the relative intersatellite distance changes and it can be inverted to estimate the mass change near the surface of the Earth. Over the continental land surface, the hydrological processes are the major driver of the variation in mass anomaly at monthly to decadal scales. However various other signals such as oceanic and atmospheric variations, high frequency tidal mass changes, systemic correlated errors, etc. are also part of the obtained GRACE signals [@humphrey2023using]. Some of the unwanted signals, such as the high frequency tidal mass changes in the ocean and the atmosphere, are modelled and removed at level 1 processing `(Flechtner, 2007)`, while noise is still present at level 2 and it requires filtering [@wahr1998time; @vishwakarma2017understanding]. The choice of filter and/or subsequent steps to counter the signal loss due to filtering have an impact on the quality of GRACE products that are of interest to hydrologists `(Humphrey et al., 2023; Vishwakarma, 2020)`. The estimated hydrological signal is represented in terms of  `total water storage anomaly` (`TWSA`), which is the change in the water mass over a vertical column. Conventionally, it is represented in terms of `equivalent water height` (`m`). <br>
 
 <i>Table 1: Summary of GRACE satellite mission [[source]](https://www2.csr.utexas.edu/grace/mission/mdetail.html)</i>
 
@@ -237,6 +237,10 @@ The authors would like to thank Dr.-Ing. Markus Antoni and Clara Buetzler, Insti
 
 # Citations
 
+Citations to entries in paper.bib should be in
+[rMarkdown](http://rmarkdown.rstudio.com/authoring_bibliographies_and_citations.html)
+format.
+
 - Antoni, M. (2022). A review of different mascon approaches for regional gravity field modelling since 1968. History of Geo-and Space Sciences, 13(2), 205-217. https://hgss.copernicus.org/articles/13/205/2022/ 
 - Chao, B. F., & Gross, R. S. (1987). Changes in the Earth's rotation and low-degree gravitational field induced by earthquakes. Geophysical Journal International, 91(3), 569-596. DOI 10.1111/j.1365-246X.197.tb01659.x 
 - Darbeheshti, N., Wöske, F., Weigelt, M., Mccullough, C., & Wu, H. (2018). GRACETOOLS—GRACE Gravity Field Recovery Tools. Geosciences, 8(9), 350. https://www.mdpi.com/2076-3263/8/9/350