Are the value of my benefits affected by the volatility in the financial markets?

No, the LGPS is a defined benefit pension scheme which means your pension is based on your salary and how long you’ve paid in. Your pension is not linked to stock market performance, so both your contributions and your pension, whether in payment or not, will be unaffected.
The only exception to this is Additional Voluntary Contributions (AVCs). If you have an AVC, it is possible the value may have reduced – this will depend on the funds you have chosen to invest in. You should contact your AVC provider for more information about this.